72687649 has 2 divisors, whose sum is σ = 72687650. Its totient is φ = 72687648.

The previous prime is 72687611. The next prime is 72687683. The reversal of 72687649 is 94678627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38254225 + 34433424 = 6185^2 + 5868^2 .

It is a cyclic number.

It is not a de Polignac number, because 72687649 - 2¹¹ = 72685601 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (72687689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36343824 + 36343825.

It is an arithmetic number, because the mean of its divisors is an integer number (36343825).

Almost surely, 2^72687649 is an apocalyptic number.

It is an amenable number.

72687649 is a deficient number, since it is larger than the sum of its proper divisors (1).

72687649 is an equidigital number, since it uses as much as digits as its factorization.

72687649 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1016064, while the sum is 49.

The square root of 72687649 is about 8525.7051907745. The cubic root of 72687649 is about 417.3369848958.

The spelling of 72687649 in words is "seventy-two million, six hundred eighty-seven thousand, six hundred forty-nine".