221972 has 12 divisors (see below), whose sum is σ = 391776. Its totient is φ = 110040.

The previous prime is 221957. The next prime is 221987. The reversal of 221972 is 279122.

It is an interprime number because it is at equal distance from previous prime (221957) and next prime (221987).

It is a congruent number.

It is an unprimeable number.

221972 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 713 + ... + 975.

It is an arithmetic number, because the mean of its divisors is an integer number (32648).

2²²¹⁹⁷² is an apocalyptic number.

It is an amenable number.

221972 is a deficient number, since it is larger than the sum of its proper divisors (169804).

221972 is a wasteful number, since it uses less digits than its factorization.

221972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 478 (or 476 counting only the distinct ones).

The product of its digits is 504, while the sum is 23.

The square root of 221972 is about 471.1390452934. The cubic root of 221972 is about 60.5479436919.

The spelling of 221972 in words is "two hundred twenty-one thousand, nine hundred seventy-two".