39972557 has 2 divisors, whose sum is σ = 39972558. Its totient is φ = 39972556.

The previous prime is 39972529. The next prime is 39972563. The reversal of 39972557 is 75527993.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21473956 + 18498601 = 4634^2 + 4301^2 .

It is an emirp because it is prime and its reverse (75527993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39972557 - 2⁸ = 39972301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39972577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19986278 + 19986279.

It is an arithmetic number, because the mean of its divisors is an integer number (19986279).

Almost surely, 2^39972557 is an apocalyptic number.

It is an amenable number.

39972557 is a deficient number, since it is larger than the sum of its proper divisors (1).

39972557 is an equidigital number, since it uses as much as digits as its factorization.

39972557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 595350, while the sum is 47.

The square root of 39972557 is about 6322.3853884432. The cubic root of 39972557 is about 341.9169599924.

The spelling of 39972557 in words is "thirty-nine million, nine hundred seventy-two thousand, five hundred fifty-seven".