72172815307 has 2 divisors, whose sum is σ = 72172815308. Its totient is φ = 72172815306.

The previous prime is 72172815287. The next prime is 72172815311. The reversal of 72172815307 is 70351827127.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 72172815307 - 2¹¹ = 72172813259 is a prime.

It is not a weakly prime, because it can be changed into another prime (72172815907) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36086407653 + 36086407654.

It is an arithmetic number, because the mean of its divisors is an integer number (36086407654).

Almost surely, 2^72172815307 is an apocalyptic number.

72172815307 is a deficient number, since it is larger than the sum of its proper divisors (1).

72172815307 is an equidigital number, since it uses as much as digits as its factorization.

72172815307 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164640, while the sum is 43.

The spelling of 72172815307 in words is "seventy-two billion, one hundred seventy-two million, eight hundred fifteen thousand, three hundred seven".