25656442020 has 144 divisors (see below), whose sum is σ = 85014401472. Its totient is φ = 6211326720.

The previous prime is 25656442003. The next prime is 25656442033. The reversal of 25656442020 is 2024465652.

25656442020 is a `hidden beast` number, since 2 + 5 + 6 + 5 + 644 + 2 + 0 + 2 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1522159 + ... + 1538921.

It is an arithmetic number, because the mean of its divisors is an integer number (590377788).

Almost surely, 2^25656442020 is an apocalyptic number.

25656442020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 25656442020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42507200736).

25656442020 is an abundant number, since it is smaller than the sum of its proper divisors (59357959452).

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

25656442020 is a wasteful number, since it uses less digits than its factorization.

25656442020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17562 (or 17557 counting only the distinct ones).

The product of its (nonzero) digits is 115200, while the sum is 36.

The spelling of 25656442020 in words is "twenty-five billion, six hundred fifty-six million, four hundred forty-two thousand, twenty".