78618042400 has 72 divisors (see below), whose sum is σ = 192251109204. Its totient is φ = 31393996800.

The previous prime is 78618042397. The next prime is 78618042401. The reversal of 78618042400 is 424081687.

It can be written as a sum of positive squares in 6 ways, for example, as 40059221904 + 38558820496 = 200148^2 + 196364^2 .

It is a Harshad number since it is a multiple of its sum of digits (40).

It is not an unprimeable number, because it can be changed into a prime (78618042401) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 391540 + ... + 557260.

Almost surely, 2^78618042400 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 78618042400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96125554602).

78618042400 is an abundant number, since it is smaller than the sum of its proper divisors (113633066804).

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

78618042400 is a wasteful number, since it uses less digits than its factorization.

78618042400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 166334 (or 166321 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 40.

The spelling of 78618042400 in words is "seventy-eight billion, six hundred eighteen million, forty-two thousand, four hundred".