1991845350 has 192 divisors, whose sum is σ = 6045684480. Its totient is φ = 478195200.

The previous prime is 1991845343. The next prime is 1991845357. The reversal of 1991845350 is 535481991.

1991845350 is a `hidden beast` number, since 199 + 1 + 8 + 453 + 5 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1991845343) and next prime (1991845357).

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a junction number, because it is equal to n+sod(n) for n = 1991845296 and 1991845305.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991845357) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1677457 + ... + 1678643.

It is an arithmetic number, because the mean of its divisors is an integer number (31487940).

Almost surely, 2^1991845350 is an apocalyptic number.

1991845350 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1991845350, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3022842240).

1991845350 is an abundant number, since it is smaller than the sum of its proper divisors (4053839130).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1991845350 is a wasteful number, since it uses less digits than its factorization.

1991845350 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1332 (or 1321 counting only the distinct ones).

The product of its (nonzero) digits is 194400, while the sum is 45.

The square root of 1991845350 is about 44630.0946671638. The cubic root of 1991845350 is about 1258.2063481153.

The spelling of 1991845350 in words is "one billion, nine hundred ninety-one million, eight hundred forty-five thousand, three hundred fifty".