72078756531 has 16 divisors (see below), whose sum is σ = 96371493120. Its totient is φ = 47919416480.

The previous prime is 72078756481. The next prime is 72078756557. The reversal of 72078756531 is 13565787027.

It is a cyclic number.

It is not a de Polignac number, because 72078756531 - 2⁷ = 72078756403 is a prime.

It is a super-2 number, since 2×72078756531² (a number of 23 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (72078556531) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1940746 + ... + 1977536.

It is an arithmetic number, because the mean of its divisors is an integer number (6023218320).

Almost surely, 2^72078756531 is an apocalyptic number.

72078756531 is a deficient number, since it is larger than the sum of its proper divisors (24292736589).

72078756531 is a wasteful number, since it uses less digits than its factorization.

72078756531 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38586.

The product of its (nonzero) digits is 2469600, while the sum is 51.

The spelling of 72078756531 in words is "seventy-two billion, seventy-eight million, seven hundred fifty-six thousand, five hundred thirty-one".