72110100521 has 2 divisors, whose sum is σ = 72110100522. Its totient is φ = 72110100520.

The previous prime is 72110100497. The next prime is 72110100551. The reversal of 72110100521 is 12500101127.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 67931124496 + 4178976025 = 260636^2 + 64645^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72110100521 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72110100493 and 72110100502.

It is not a weakly prime, because it can be changed into another prime (72110100551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36055050260 + 36055050261.

It is an arithmetic number, because the mean of its divisors is an integer number (36055050261).

Almost surely, 2^72110100521 is an apocalyptic number.

It is an amenable number.

72110100521 is a deficient number, since it is larger than the sum of its proper divisors (1).

72110100521 is an equidigital number, since it uses as much as digits as its factorization.

72110100521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 140, while the sum is 20.

Adding to 72110100521 its reverse (12500101127), we get a palindrome (84610201648).

The spelling of 72110100521 in words is "seventy-two billion, one hundred ten million, one hundred thousand, five hundred twenty-one".