16215664 has 40 divisors (see below), whose sum is σ = 33904080. Its totient is φ = 7488000.

The previous prime is 16215659. The next prime is 16215677. The reversal of 16215664 is 46651261.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11814 + ... + 13114.

It is an arithmetic number, because the mean of its divisors is an integer number (847602).

Almost surely, 2^16215664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16215664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16952040).

16215664 is an abundant number, since it is smaller than the sum of its proper divisors (17688416).

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

16215664 is a wasteful number, since it uses less digits than its factorization.

16215664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1369 (or 1363 counting only the distinct ones).

The product of its digits is 8640, while the sum is 31.

The square root of 16215664 is about 4026.8677653978. The cubic root of 16215664 is about 253.1113259697. Note that the first 3 decimals are identical.

The spelling of 16215664 in words is "sixteen million, two hundred fifteen thousand, six hundred sixty-four".