16522621 has 4 divisors (see below), whose sum is σ = 16906912. Its totient is φ = 16138332.

The previous prime is 16522603. The next prime is 16522651. The reversal of 16522621 is 12622561.

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 16522621 - 2¹⁷ = 16391549 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16522651) 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, 192081 + ... + 192166.

It is an arithmetic number, because the mean of its divisors is an integer number (4226728).

Almost surely, 2^16522621 is an apocalyptic number.

It is an amenable number.

16522621 is a deficient number, since it is larger than the sum of its proper divisors (384291).

16522621 is an equidigital number, since it uses as much as digits as its factorization.

16522621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 384290.

The product of its digits is 1440, while the sum is 25.

The square root of 16522621 is about 4064.8027012390. The cubic root of 16522621 is about 254.6984568360.

The spelling of 16522621 in words is "sixteen million, five hundred twenty-two thousand, six hundred twenty-one".