221493388 has 24 divisors (see below), whose sum is σ = 405614720. Its totient is φ = 105701760.

The previous prime is 221493367. The next prime is 221493397. The reversal of 221493388 is 883394122.

221493388 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 221493388.

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, 3183 + ... + 21286.

Almost surely, 2^221493388 is an apocalyptic number.

It is an amenable number.

221493388 is a deficient number, since it is larger than the sum of its proper divisors (184121332).

221493388 is a wasteful number, since it uses less digits than its factorization.

221493388 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24577 (or 24575 counting only the distinct ones).

The product of its digits is 82944, while the sum is 40.

The square root of 221493388 is about 14882.6539299951. The cubic root of 221493388 is about 605.0439491785.

The spelling of 221493388 in words is "two hundred twenty-one million, four hundred ninety-three thousand, three hundred eighty-eight".