221664124 has 24 divisors (see below), whose sum is σ = 424884096. Its totient is φ = 100350000.

The previous prime is 221664119. The next prime is 221664161. The reversal of 221664124 is 421466122.

It is a junction number, because it is equal to n+sod(n) for n = 221664092 and 221664101.

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, 1009 + ... + 21079.

It is an arithmetic number, because the mean of its divisors is an integer number (17703504).

Almost surely, 2^221664124 is an apocalyptic number.

It is an amenable number.

221664124 is a deficient number, since it is larger than the sum of its proper divisors (203219972).

221664124 is a wasteful number, since it uses less digits than its factorization.

221664124 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20337 (or 20335 counting only the distinct ones).

The product of its digits is 4608, while the sum is 28.

The square root of 221664124 is about 14888.3888987358. The cubic root of 221664124 is about 605.1993733091.

The spelling of 221664124 in words is "two hundred twenty-one million, six hundred sixty-four thousand, one hundred twenty-four".