20392857 has 16 divisors (see below), whose sum is σ = 30665280. Its totient is φ = 13391136.

The previous prime is 20392847. The next prime is 20392873. The reversal of 20392857 is 75829302.

It is a happy number.

It is not a de Polignac number, because 20392857 - 2¹² = 20388761 is a prime.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (20392807) 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, 3828 + ... + 7445.

It is an arithmetic number, because the mean of its divisors is an integer number (1916580).

Almost surely, 2^20392857 is an apocalyptic number.

20392857 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

It is an amenable number.

20392857 is a deficient number, since it is larger than the sum of its proper divisors (10272423).

20392857 is a wasteful number, since it uses less digits than its factorization.

20392857 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11349 (or 11343 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 20392857 is about 4515.8451036323. The cubic root of 20392857 is about 273.2075465576.

The spelling of 20392857 in words is "twenty million, three hundred ninety-two thousand, eight hundred fifty-seven".