20900399 has 24 divisors (see below), whose sum is σ = 24946560. Its totient is φ = 17420832.

The previous prime is 20900389. The next prime is 20900401. The reversal of 20900399 is 99300902.

It is a de Polignac number, because none of the positive numbers 2^k-20900399 is a prime.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20900339) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 73712 + ... + 73994.

It is an arithmetic number, because the mean of its divisors is an integer number (1039440).

Almost surely, 2^20900399 is an apocalyptic number.

20900399 is a deficient number, since it is larger than the sum of its proper divisors (4046161).

20900399 is a wasteful number, since it uses less digits than its factorization.

20900399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 351 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 4374, while the sum is 32.

The square root of 20900399 is about 4571.6954185510. The cubic root of 20900399 is about 275.4555490793.

The spelling of 20900399 in words is "twenty million, nine hundred thousand, three hundred ninety-nine".