15625436640 has 288 divisors, whose sum is σ = 55973060640. Its totient is φ = 3656970240.

The previous prime is 15625436591. The next prime is 15625436681. The reversal of 15625436640 is 4663452651.

It is a junction number, because it is equal to n+sod(n) for n = 15625436592 and 15625436601.

It is a congruent number.

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, 1679682 + ... + 1688958.

It is an arithmetic number, because the mean of its divisors is an integer number (194350905).

Almost surely, 2^15625436640 is an apocalyptic number.

15625436640 is a gapful number since it is divisible by the number (10) 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 15625436640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27986530320).

15625436640 is an abundant number, since it is smaller than the sum of its proper divisors (40347624000).

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

15625436640 is a wasteful number, since it uses less digits than its factorization.

15625436640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9346 (or 9327 counting only the distinct ones).

The product of its (nonzero) digits is 518400, while the sum is 42.

The spelling of 15625436640 in words is "fifteen billion, six hundred twenty-five million, four hundred thirty-six thousand, six hundred forty".