18961958400 has 960 divisors, whose sum is σ = 80227293696. Its totient is φ = 3865804800.

The previous prime is 18961958383. The next prime is 18961958419. The reversal of 18961958400 is 485916981.

It is a tau number, because it is divible by the number of its divisors (960).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 357772774 + ... + 357772826.

Almost surely, 2^18961958400 is an apocalyptic number.

18961958400 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18961958400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40113646848).

18961958400 is an abundant number, since it is smaller than the sum of its proper divisors (61265335296).

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

18961958400 is an equidigital number, since it uses as much as digits as its factorization.

18961958400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124 (or 81 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 51.

The spelling of 18961958400 in words is "eighteen billion, nine hundred sixty-one million, nine hundred fifty-eight thousand, four hundred".