25449678840 has 32 divisors (see below), whose sum is σ = 76349036880. Its totient is φ = 6786580992.

The previous prime is 25449678817. The next prime is 25449678841. The reversal of 25449678840 is 4887694452.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (25449678841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 106040209 + ... + 106040448.

Almost surely, 2^25449678840 is an apocalyptic number.

25449678840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25449678840 is an abundant number, since it is smaller than the sum of its proper divisors (50899358040).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

25449678840 is a wasteful number, since it uses less digits than its factorization.

25449678840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 212080671 (or 212080667 counting only the distinct ones).

The product of its (nonzero) digits is 15482880, while the sum is 57.

It can be divided in two parts, 254496 and 78840, that added together give a triangular number (333336 = T₈₁₆).

The spelling of 25449678840 in words is "twenty-five billion, four hundred forty-nine million, six hundred seventy-eight thousand, eight hundred forty".