221531332 has 24 divisors (see below), whose sum is σ = 436568832. Its totient is φ = 97447200.

The previous prime is 221531309. The next prime is 221531341. The reversal of 221531332 is 233135122.

It is a super-2 number, since 2×221531332² = 98152262115388448, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (22).

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, 79843 + ... + 82570.

It is an arithmetic number, because the mean of its divisors is an integer number (18190368).

Almost surely, 2^221531332 is an apocalyptic number.

221531332 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

221531332 is a deficient number, since it is larger than the sum of its proper divisors (215037500).

221531332 is a wasteful number, since it uses less digits than its factorization.

221531332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162459 (or 162457 counting only the distinct ones).

The product of its digits is 1080, while the sum is 22.

The square root of 221531332 is about 14883.9286480418. The cubic root of 221531332 is about 605.0784972027.

Adding to 221531332 its reverse (233135122), we get a palindrome (454666454).

The spelling of 221531332 in words is "two hundred twenty-one million, five hundred thirty-one thousand, three hundred thirty-two".