15421904640 has 324 divisors, whose sum is σ = 54429606504. Its totient is φ = 4030967808.

The previous prime is 15421904623. The next prime is 15421904683. The reversal of 15421904640 is 4640912451.

15421904640 is a `hidden beast` number, since 1 + 5 + 4 + 2 + 1 + 9 + 0 + 4 + 640 = 666.

15421904640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a junction number, because it is equal to n+sod(n) for n = 15421904595 and 15421904604.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 121432257 + ... + 121432383.

Almost surely, 2^15421904640 is an apocalyptic number.

15421904640 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 15421904640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27214803252).

15421904640 is an abundant number, since it is smaller than the sum of its proper divisors (39007701864).

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

15421904640 is an equidigital number, since it uses as much as digits as its factorization.

15421904640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 364 (or 220 counting only the distinct ones).

The product of its (nonzero) digits is 34560, while the sum is 36.

The spelling of 15421904640 in words is "fifteen billion, four hundred twenty-one million, nine hundred four thousand, six hundred forty".