25705412639 has 4 divisors (see below), whose sum is σ = 25954979856. Its totient is φ = 25455845424.

The previous prime is 25705412633. The next prime is 25705412641. The reversal of 25705412639 is 93621450752.

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

It is a cyclic number.

It is not a de Polignac number, because 25705412639 - 2¹² = 25705408543 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 25705412639.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25705412633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124783454 + ... + 124783659.

It is an arithmetic number, because the mean of its divisors is an integer number (6488744964).

Almost surely, 2^25705412639 is an apocalyptic number.

25705412639 is a deficient number, since it is larger than the sum of its proper divisors (249567217).

25705412639 is a wasteful number, since it uses less digits than its factorization.

25705412639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 249567216.

The product of its (nonzero) digits is 453600, while the sum is 44.

The spelling of 25705412639 in words is "twenty-five billion, seven hundred five million, four hundred twelve thousand, six hundred thirty-nine".