25557649620 has 48 divisors (see below), whose sum is σ = 71678261760. Its totient is φ = 6804245376.

The previous prime is 25557649603. The next prime is 25557649631. The reversal of 25557649620 is 2694675552.

It is a happy number.

It is a super-2 number, since 2×25557649620² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

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 in 15 ways as a sum of consecutive naturals, for example, 310660 + ... + 384219.

It is an arithmetic number, because the mean of its divisors is an integer number (1493297120).

Almost surely, 2^25557649620 is an apocalyptic number.

25557649620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

25557649620 is an abundant number, since it is smaller than the sum of its proper divisors (46120612140).

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

25557649620 is a wasteful number, since it uses less digits than its factorization.

25557649620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695504 (or 695502 counting only the distinct ones).

The product of its (nonzero) digits is 4536000, while the sum is 51.

The spelling of 25557649620 in words is "twenty-five billion, five hundred fifty-seven million, six hundred forty-nine thousand, six hundred twenty".