20332991 has 6 divisors (see below), whose sum is σ = 23652720. Its totient is φ = 17428236.

The previous prime is 20332981. The next prime is 20333009. The reversal of 20332991 is 19923302.

It is not a de Polignac number, because 20332991 - 2¹⁰ = 20331967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20332951) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 207431 + ... + 207528.

It is an arithmetic number, because the mean of its divisors is an integer number (3942120).

Almost surely, 2^20332991 is an apocalyptic number.

20332991 is a deficient number, since it is larger than the sum of its proper divisors (3319729).

20332991 is an equidigital number, since it uses as much as digits as its factorization.

20332991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 414973 (or 414966 counting only the distinct ones).

The product of its (nonzero) digits is 2916, while the sum is 29.

The square root of 20332991 is about 4509.2117936509. The cubic root of 20332991 is about 272.9399385732.

The spelling of 20332991 in words is "twenty million, three hundred thirty-two thousand, nine hundred ninety-one".