39972781925 has 6 divisors (see below), whose sum is σ = 49566249618. Its totient is φ = 31978225520.

The previous prime is 39972781903. The next prime is 39972781931. The reversal of 39972781925 is 52918727993.

39972781925 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 10942415236 + 29030366689 = 104606^2 + 170383^2 .

It is a de Polignac number, because none of the positive numbers 2^k-39972781925 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 799455614 + ... + 799455663.

It is an arithmetic number, because the mean of its divisors is an integer number (8261041603).

Almost surely, 2^39972781925 is an apocalyptic number.

It is an amenable number.

39972781925 is a deficient number, since it is larger than the sum of its proper divisors (9593467693).

39972781925 is a wasteful number, since it uses less digits than its factorization.

39972781925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1598911287 (or 1598911282 counting only the distinct ones).

The product of its digits is 17146080, while the sum is 62.

The spelling of 39972781925 in words is "thirty-nine billion, nine hundred seventy-two million, seven hundred eighty-one thousand, nine hundred twenty-five".