25438277138 has 8 divisors (see below), whose sum is σ = 38158512588. Its totient is φ = 12718772944.

The previous prime is 25438277107. The next prime is 25438277149. The reversal of 25438277138 is 83177283452.

It can be written as a sum of positive squares in 2 ways, for example, as 22821238489 + 2617038649 = 151067^2 + 51157^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 85481 + ... + 241212.

Almost surely, 2^25438277138 is an apocalyptic number.

25438277138 is a deficient number, since it is larger than the sum of its proper divisors (12720235450).

25438277138 is a wasteful number, since it uses less digits than its factorization.

25438277138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 365628.

The product of its digits is 2257920, while the sum is 50.

The spelling of 25438277138 in words is "twenty-five billion, four hundred thirty-eight million, two hundred seventy-seven thousand, one hundred thirty-eight".