15421668864 has 360 divisors, whose sum is σ = 50840194680. Its totient is φ = 4141154304.

The previous prime is 15421668841. The next prime is 15421668883. The reversal of 15421668864 is 46886612451.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 21750942 + ... + 21751650.

It is an arithmetic number, because the mean of its divisors is an integer number (141222763).

Almost surely, 2^15421668864 is an apocalyptic number.

15421668864 is a gapful number since it is divisible by the number (14) 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 15421668864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25420097340).

15421668864 is an abundant number, since it is smaller than the sum of its proper divisors (35418525816).

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

15421668864 is an equidigital number, since it uses as much as digits as its factorization.

15421668864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 778 (or 738 counting only the distinct ones).

The product of its digits is 2211840, while the sum is 51.

The spelling of 15421668864 in words is "fifteen billion, four hundred twenty-one million, six hundred sixty-eight thousand, eight hundred sixty-four".