15323520421 has 4 divisors (see below), whose sum is σ = 16716567744. Its totient is φ = 13930473100.

The previous prime is 15323520343. The next prime is 15323520439. The reversal of 15323520421 is 12402532351.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 15323520421 - 2⁷ = 15323520293 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15323520421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15323520451) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 696523645 + ... + 696523666.

It is an arithmetic number, because the mean of its divisors is an integer number (4179141936).

Almost surely, 2^15323520421 is an apocalyptic number.

15323520421 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15323520421 is a deficient number, since it is larger than the sum of its proper divisors (1393047323).

15323520421 is a wasteful number, since it uses less digits than its factorization.

15323520421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1393047322.

The product of its (nonzero) digits is 7200, while the sum is 28.

The spelling of 15323520421 in words is "fifteen billion, three hundred twenty-three million, five hundred twenty thousand, four hundred twenty-one".