321320997 has 12 divisors (see below), whose sum is σ = 466177920. Its totient is φ = 213268968.

The previous prime is 321320981. The next prime is 321321001. The reversal of 321320997 is 799023123.

321320997 is a `hidden beast` number, since 321 + 320 + 9 + 9 + 7 = 666.

It is not a de Polignac number, because 321320997 - 2⁴ = 321320981 is a prime.

It is a super-2 number, since 2×321320997² = 206494366226148018, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (321320947) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 76597 + ... + 80682.

It is an arithmetic number, because the mean of its divisors is an integer number (38848160).

Almost surely, 2^321320997 is an apocalyptic number.

It is an amenable number.

321320997 is a deficient number, since it is larger than the sum of its proper divisors (144856923).

321320997 is a wasteful number, since it uses less digits than its factorization.

321320997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157512 (or 157509 counting only the distinct ones).

The product of its (nonzero) digits is 20412, while the sum is 36.

The square root of 321320997 is about 17925.4287814825. The cubic root of 321320997 is about 684.9302836324.

The spelling of 321320997 in words is "three hundred twenty-one million, three hundred twenty thousand, nine hundred ninety-seven".