20290139 has 2 divisors, whose sum is σ = 20290140. Its totient is φ = 20290138.

The previous prime is 20290133. The next prime is 20290147. The reversal of 20290139 is 93109202.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20290139 - 2²⁴ = 3512923 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20290133) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10145069 + 10145070.

It is an arithmetic number, because the mean of its divisors is an integer number (10145070).

Almost surely, 2^20290139 is an apocalyptic number.

20290139 is a deficient number, since it is larger than the sum of its proper divisors (1).

20290139 is an equidigital number, since it uses as much as digits as its factorization.

20290139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 26.

The square root of 20290139 is about 4504.4576810089. The cubic root of 20290139 is about 272.7480624186.

The spelling of 20290139 in words is "twenty million, two hundred ninety thousand, one hundred thirty-nine".