1818661950 has 288 divisors, whose sum is σ = 6140678400. Its totient is φ = 393543360.

The previous prime is 1818661939. The next prime is 1818661979. The reversal of 1818661950 is 591668181.

1818661950 is a `hidden beast` number, since 18 + 18 + 6 + 619 + 5 + 0 = 666.

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 = 1818661896 and 1818661905.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 1256127 + ... + 1257573.

It is an arithmetic number, because the mean of its divisors is an integer number (21321800).

Almost surely, 2^1818661950 is an apocalyptic number.

1818661950 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 1818661950, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3070339200).

1818661950 is an abundant number, since it is smaller than the sum of its proper divisors (4322016450).

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

1818661950 is a wasteful number, since it uses less digits than its factorization.

1818661950 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1501 (or 1483 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 45.

The square root of 1818661950 is about 42645.7729441031. The cubic root of 1818661950 is about 1220.6298704858.

The spelling of 1818661950 in words is "one billion, eight hundred eighteen million, six hundred sixty-one thousand, nine hundred fifty".