25569949138 has 4 divisors (see below), whose sum is σ = 38354923710. Its totient is φ = 12784974568.

The previous prime is 25569949129. The next prime is 25569949151. The reversal of 25569949138 is 83194996552.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 24252767289 + 1317181849 = 155733^2 + 36293^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6392487283 + ... + 6392487286.

Almost surely, 2^25569949138 is an apocalyptic number.

25569949138 is a deficient number, since it is larger than the sum of its proper divisors (12784974572).

25569949138 is a wasteful number, since it uses less digits than its factorization.

25569949138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12784974571.

The product of its digits is 20995200, while the sum is 61.

The spelling of 25569949138 in words is "twenty-five billion, five hundred sixty-nine million, nine hundred forty-nine thousand, one hundred thirty-eight".