20850399 has 16 divisors (see below), whose sum is σ = 31609600. Its totient is φ = 13576248.

The previous prime is 20850367. The next prime is 20850407. The reversal of 20850399 is 99305802.

It is not a de Polignac number, because 20850399 - 2⁵ = 20850367 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20850799) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7819 + ... + 10140.

It is an arithmetic number, because the mean of its divisors is an integer number (1975600).

Almost surely, 2^20850399 is an apocalyptic number.

20850399 is a deficient number, since it is larger than the sum of its proper divisors (10759201).

20850399 is a wasteful number, since it uses less digits than its factorization.

20850399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18011 (or 18005 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 36.

The square root of 20850399 is about 4566.2237133106. The cubic root of 20850399 is about 275.2357163552.

The spelling of 20850399 in words is "twenty million, eight hundred fifty thousand, three hundred ninety-nine".