221976836 has 12 divisors (see below), whose sum is σ = 397493712. Its totient is φ = 108407208.

The previous prime is 221976809. The next prime is 221976847. The reversal of 221976836 is 638679122.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 645110 + ... + 645453.

It is an arithmetic number, because the mean of its divisors is an integer number (33124476).

Almost surely, 2^221976836 is an apocalyptic number.

It is an amenable number.

221976836 is a deficient number, since it is larger than the sum of its proper divisors (175516876).

221976836 is a wasteful number, since it uses less digits than its factorization.

221976836 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1290610 (or 1290608 counting only the distinct ones).

The product of its digits is 217728, while the sum is 44.

The square root of 221976836 is about 14898.8870725299. The cubic root of 221976836 is about 605.4838339856.

The spelling of 221976836 in words is "two hundred twenty-one million, nine hundred seventy-six thousand, eight hundred thirty-six".