20813739 has 4 divisors (see below), whose sum is σ = 27751656. Its totient is φ = 13875824.

The previous prime is 20813731. The next prime is 20813753. The reversal of 20813739 is 93731802.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20813739 - 2³ = 20813731 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20813731) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3468954 + ... + 3468959.

It is an arithmetic number, because the mean of its divisors is an integer number (6937914).

Almost surely, 2^20813739 is an apocalyptic number.

20813739 is a deficient number, since it is larger than the sum of its proper divisors (6937917).

20813739 is an equidigital number, since it uses as much as digits as its factorization.

20813739 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6937916.

The product of its (nonzero) digits is 9072, while the sum is 33.

The square root of 20813739 is about 4562.2076892662. The cubic root of 20813739 is about 275.0743115979.

The spelling of 20813739 in words is "twenty million, eight hundred thirteen thousand, seven hundred thirty-nine".