78111920400 has 120 divisors (see below), whose sum is σ = 250341730080. Its totient is φ = 20819589120.

The previous prime is 78111920353. The next prime is 78111920449. The reversal of 78111920400 is 402911187.

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-2 number, since 2×78111920400² (a number of 23 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2599864 + ... + 2629736.

It is an arithmetic number, because the mean of its divisors is an integer number (2086181084).

Almost surely, 2^78111920400 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 78111920400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125170865040).

78111920400 is an abundant number, since it is smaller than the sum of its proper divisors (172229809680).

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

78111920400 is a wasteful number, since it uses less digits than its factorization.

78111920400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32073 (or 32062 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 33.

The spelling of 78111920400 in words is "seventy-eight billion, one hundred eleven million, nine hundred twenty thousand, four hundred".