78436874640 has 160 divisors (see below), whose sum is σ = 257026406400. Its totient is φ = 19732446720.

The previous prime is 78436874639. The next prime is 78436874641. The reversal of 78436874640 is 4647863487.

It is an interprime number because it is at equal distance from previous prime (78436874639) and next prime (78436874641).

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (78436874641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1053855 + ... + 1125825.

It is an arithmetic number, because the mean of its divisors is an integer number (1606415040).

Almost surely, 2^78436874640 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 78436874640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (128513203200).

78436874640 is an abundant number, since it is smaller than the sum of its proper divisors (178589531760).

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

78436874640 is a wasteful number, since it uses less digits than its factorization.

78436874640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72245 (or 72239 counting only the distinct ones).

The product of its (nonzero) digits is 21676032, while the sum is 57.

The spelling of 78436874640 in words is "seventy-eight billion, four hundred thirty-six million, eight hundred seventy-four thousand, six hundred forty".