20901539 has 6 divisors (see below), whose sum is σ = 22059900. Its totient is φ = 19801116.

The previous prime is 20901509. The next prime is 20901581. The reversal of 20901539 is 93510902.

It is a de Polignac number, because none of the positive numbers 2^k-20901539 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20901509) 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, 28589 + ... + 29310.

It is an arithmetic number, because the mean of its divisors is an integer number (3676650).

Almost surely, 2^20901539 is an apocalyptic number.

20901539 is a deficient number, since it is larger than the sum of its proper divisors (1158361).

20901539 is an equidigital number, since it uses as much as digits as its factorization.

20901539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57937 (or 57918 counting only the distinct ones).

The product of its (nonzero) digits is 2430, while the sum is 29.

The square root of 20901539 is about 4571.8200970729. The cubic root of 20901539 is about 275.4605571754.

The spelling of 20901539 in words is "twenty million, nine hundred one thousand, five hundred thirty-nine".