20290331 has 2 divisors, whose sum is σ = 20290332. Its totient is φ = 20290330.

The previous prime is 20290327. The next prime is 20290349. The reversal of 20290331 is 13309202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20290331 - 2² = 20290327 is a prime.

It is a super-2 number, since 2×20290331² = 823395064179122, which contains 22 as substring.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (20290931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10145165 + 10145166.

It is an arithmetic number, because the mean of its divisors is an integer number (10145166).

Almost surely, 2^20290331 is an apocalyptic number.

20290331 is a deficient number, since it is larger than the sum of its proper divisors (1).

20290331 is an equidigital number, since it uses as much as digits as its factorization.

20290331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 324, while the sum is 20.

The square root of 20290331 is about 4504.4789931800. The cubic root of 20290331 is about 272.7489227291.

Adding to 20290331 its reverse (13309202), we get a palindrome (33599533).

The spelling of 20290331 in words is "twenty million, two hundred ninety thousand, three hundred thirty-one".