25638435900 has 1080 divisors, whose sum is σ = 108285548448. Its totient is φ = 5132160000.

The previous prime is 25638435853. The next prime is 25638435919. The reversal of 25638435900 is 953483652.

25638435900 is a `hidden beast` number, since 2 + 5 + 638 + 4 + 3 + 5 + 9 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 359 ways as a sum of consecutive naturals, for example, 253845850 + ... + 253845950.

Almost surely, 2^25638435900 is an apocalyptic number.

25638435900 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 25638435900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (54142774224).

25638435900 is an abundant number, since it is smaller than the sum of its proper divisors (82647112548).

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

25638435900 is a wasteful number, since it uses less digits than its factorization.

25638435900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 193 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 45.

The spelling of 25638435900 in words is "twenty-five billion, six hundred thirty-eight million, four hundred thirty-five thousand, nine hundred".