291221132 has 48 divisors (see below), whose sum is σ = 558348000. Its totient is φ = 132378624.

The previous prime is 291221123. The next prime is 291221149. The reversal of 291221132 is 231122192.

It is a happy number.

It is a super-2 number, since 2×291221132² = 169619495446722848, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 291221098 and 291221107.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 504428 + ... + 505004.

It is an arithmetic number, because the mean of its divisors is an integer number (11632250).

Almost surely, 2^291221132 is an apocalyptic number.

It is an amenable number.

291221132 is a deficient number, since it is larger than the sum of its proper divisors (267126868).

291221132 is a wasteful number, since it uses less digits than its factorization.

291221132 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 858 (or 856 counting only the distinct ones).

The product of its digits is 432, while the sum is 23.

The square root of 291221132 is about 17065.2023720787. The cubic root of 291221132 is about 662.8383515301.

The spelling of 291221132 in words is "two hundred ninety-one million, two hundred twenty-one thousand, one hundred thirty-two".