20399013 has 16 divisors (see below), whose sum is σ = 30307200. Its totient is φ = 13560480.

The previous prime is 20399009. The next prime is 20399033. The reversal of 20399013 is 31099302.

It is not a de Polignac number, because 20399013 - 2² = 20399009 is a prime.

It is a super-2 number, since 2×20399013² = 832239462748338, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20399033) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10993 + ... + 12713.

It is an arithmetic number, because the mean of its divisors is an integer number (1894200).

Almost surely, 2^20399013 is an apocalyptic number.

It is an amenable number.

20399013 is a deficient number, since it is larger than the sum of its proper divisors (9908187).

20399013 is a wasteful number, since it uses less digits than its factorization.

20399013 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2169 (or 2163 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 27.

The square root of 20399013 is about 4516.5266521964. The cubic root of 20399013 is about 273.2350348827.

The spelling of 20399013 in words is "twenty million, three hundred ninety-nine thousand, thirteen".