16221656 has 16 divisors (see below), whose sum is σ = 33180840. Its totient is φ = 7373440.

The previous prime is 16221641. The next prime is 16221659. The reversal of 16221656 is 65612261.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221659) 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, 92081 + ... + 92256.

Almost surely, 2^16221656 is an apocalyptic number.

It is an amenable number.

16221656 is an abundant number, since it is smaller than the sum of its proper divisors (16959184).

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

16221656 is a wasteful number, since it uses less digits than its factorization.

16221656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 184354 (or 184350 counting only the distinct ones).

The product of its digits is 4320, while the sum is 29.

The square root of 16221656 is about 4027.6116992580. The cubic root of 16221656 is about 253.1424986328.

The spelling of 16221656 in words is "sixteen million, two hundred twenty-one thousand, six hundred fifty-six".