72387257 has 2 divisors, whose sum is σ = 72387258. Its totient is φ = 72387256.

The previous prime is 72387253. The next prime is 72387299. The reversal of 72387257 is 75278327.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38700841 + 33686416 = 6221^2 + 5804^2 .

It is an emirp because it is prime and its reverse (75278327) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 72387257 - 2² = 72387253 is a prime.

It is not a weakly prime, because it can be changed into another prime (72387251) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 36193628 + 36193629.

It is an arithmetic number, because the mean of its divisors is an integer number (36193629).

Almost surely, 2^72387257 is an apocalyptic number.

It is an amenable number.

72387257 is a deficient number, since it is larger than the sum of its proper divisors (1).

72387257 is an equidigital number, since it uses as much as digits as its factorization.

72387257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 164640, while the sum is 41.

The square root of 72387257 is about 8508.0701101954. The cubic root of 72387257 is about 416.7612897277.

The spelling of 72387257 in words is "seventy-two million, three hundred eighty-seven thousand, two hundred fifty-seven".