72641525731 has 4 divisors (see below), whose sum is σ = 72642901464. Its totient is φ = 72640150000.

The previous prime is 72641525729. The next prime is 72641525779. The reversal of 72641525731 is 13752514627.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 13752514627 = 827 ⋅16629401.

It is a cyclic number.

It is not a de Polignac number, because 72641525731 - 2¹ = 72641525729 is a prime.

It is a super-2 number, since 2×72641525731² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (72641525711) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 605365 + ... + 715366.

It is an arithmetic number, because the mean of its divisors is an integer number (18160725366).

Almost surely, 2^72641525731 is an apocalyptic number.

72641525731 is a deficient number, since it is larger than the sum of its proper divisors (1375733).

72641525731 is a wasteful number, since it uses less digits than its factorization.

72641525731 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1375732.

The product of its digits is 352800, while the sum is 43.

The spelling of 72641525731 in words is "seventy-two billion, six hundred forty-one million, five hundred twenty-five thousand, seven hundred thirty-one".