78256131287504 has 80 divisors (see below), whose sum is σ = 157093596616320. Its totient is φ = 37720060761600.

The previous prime is 78256131287479. The next prime is 78256131287557. The reversal of 78256131287504 is 40578213165287.

It is a super-2 number, since 2×78256131287504² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4835691797 + ... + 4835707979.

It is an arithmetic number, because the mean of its divisors is an integer number (1963669957704).

Almost surely, 2^{78256131287504} 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 78256131287504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (78546798308160).

78256131287504 is an abundant number, since it is smaller than the sum of its proper divisors (78837465328816).

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

78256131287504 is a wasteful number, since it uses less digits than its factorization.

78256131287504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31788 (or 31782 counting only the distinct ones).

The product of its (nonzero) digits is 22579200, while the sum is 59.

The spelling of 78256131287504 in words is "seventy-eight trillion, two hundred fifty-six billion, one hundred thirty-one million, two hundred eighty-seven thousand, five hundred four".