72521312705109 has 6 divisors (see below), whose sum is σ = 104753007240726. Its totient is φ = 48347541803400.

The previous prime is 72521312705099. The next prime is 72521312705111. The reversal of 72521312705109 is 90150721312527.

72521312705109 is a `hidden beast` number, since 7 + 2 + 5 + 2 + 1 + 3 + 127 + 0 + 510 + 9 = 666.

It can be written as a sum of positive squares in only one way, i.e., 46984238795025 + 25537073910084 = 6854505^2 + 5053422^2 .

It is not a de Polignac number, because 72521312705109 - 2²⁴ = 72521295927893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72521312705159) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4028961816942 + ... + 4028961816959.

It is an arithmetic number, because the mean of its divisors is an integer number (17458834540121).

Almost surely, 2^{72521312705109} is an apocalyptic number.

It is an amenable number.

72521312705109 is a deficient number, since it is larger than the sum of its proper divisors (32231694535617).

72521312705109 is a wasteful number, since it uses less digits than its factorization.

72521312705109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8057923633907 (or 8057923633904 counting only the distinct ones).

The product of its (nonzero) digits is 264600, while the sum is 45.

The spelling of 72521312705109 in words is "seventy-two trillion, five hundred twenty-one billion, three hundred twelve million, seven hundred five thousand, one hundred nine".