20157859 has 4 divisors (see below), whose sum is σ = 20702704. Its totient is φ = 19613016.

The previous prime is 20157833. The next prime is 20157889. The reversal of 20157859 is 95875102.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20157859 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 544807 = 20157859 / (2 + 0 + 1 + 5 + 7 + 8 + 5 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20157889) 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 3 ways as a sum of consecutive naturals, for example, 272367 + ... + 272440.

It is an arithmetic number, because the mean of its divisors is an integer number (5175676).

Almost surely, 2^20157859 is an apocalyptic number.

20157859 is a deficient number, since it is larger than the sum of its proper divisors (544845).

20157859 is an equidigital number, since it uses as much as digits as its factorization.

20157859 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544844.

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 20157859 is about 4489.7504384988. The cubic root of 20157859 is about 272.1540496666.

The spelling of 20157859 in words is "twenty million, one hundred fifty-seven thousand, eight hundred fifty-nine".