1961889930 has 768 divisors, whose sum is σ = 7694507520. Its totient is φ = 348364800.

The previous prime is 1961889911. The next prime is 1961889931. The reversal of 1961889930 is 399881691.

1961889930 is a `hidden beast` number, since 19 + 618 + 8 + 9 + 9 + 3 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1961889931) by changing a digit.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 32162100 + ... + 32162160.

It is an arithmetic number, because the mean of its divisors is an integer number (10018890).

Almost surely, 2^1961889930 is an apocalyptic number.

1961889930 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 1961889930, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3847253760).

1961889930 is an abundant number, since it is smaller than the sum of its proper divisors (5732617590).

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

1961889930 is a wasteful number, since it uses less digits than its factorization.

1961889930 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132 (or 119 counting only the distinct ones).

The product of its (nonzero) digits is 839808, while the sum is 54.

The square root of 1961889930 is about 44293.2266830946. The cubic root of 1961889930 is about 1251.8670616096.

The spelling of 1961889930 in words is "one billion, nine hundred sixty-one million, eight hundred eighty-nine thousand, nine hundred thirty".