72665389 has 2 divisors, whose sum is σ = 72665390. Its totient is φ = 72665388.

The previous prime is 72665381. The next prime is 72665393. The reversal of 72665389 is 98356627.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68392900 + 4272489 = 8270^2 + 2067^2 .

It is an emirp because it is prime and its reverse (98356627) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72665389 - 2³ = 72665381 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (72665381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36332694 + 36332695.

It is an arithmetic number, because the mean of its divisors is an integer number (36332695).

Almost surely, 2^72665389 is an apocalyptic number.

It is an amenable number.

72665389 is a deficient number, since it is larger than the sum of its proper divisors (1).

72665389 is an equidigital number, since it uses as much as digits as its factorization.

72665389 is an evil number, because the sum of its binary digits is even.

The product of its digits is 544320, while the sum is 46.

The square root of 72665389 is about 8524.3996269532. The cubic root of 72665389 is about 417.2943785297.

The spelling of 72665389 in words is "seventy-two million, six hundred sixty-five thousand, three hundred eighty-nine".