220733721 has 32 divisors (see below), whose sum is σ = 353109120. Its totient is φ = 135473472.

The previous prime is 220733707. The next prime is 220733741. The reversal of 220733721 is 127337022.

It is a happy number.

220733721 is a `hidden beast` number, since 220 + 73 + 372 + 1 = 666.

It is not a de Polignac number, because 220733721 - 2⁹ = 220733209 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (220733701) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 197055 + ... + 198171.

It is an arithmetic number, because the mean of its divisors is an integer number (11034660).

Almost surely, 2^220733721 is an apocalyptic number.

It is an amenable number.

220733721 is a deficient number, since it is larger than the sum of its proper divisors (132375399).

220733721 is a wasteful number, since it uses less digits than its factorization.

220733721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1702 (or 1696 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 27.

The square root of 220733721 is about 14857.1101160354. The cubic root of 220733721 is about 604.3514403205.

The spelling of 220733721 in words is "two hundred twenty million, seven hundred thirty-three thousand, seven hundred twenty-one".