20851079 has 6 divisors (see below), whose sum is σ = 20996280. Its totient is φ = 20706720.

The previous prime is 20851007. The next prime is 20851097. The reversal of 20851079 is 97015802.

It is a de Polignac number, because none of the positive numbers 2^k-20851079 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 (20851679) 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 5 ways as a sum of consecutive naturals, for example, 57902 + ... + 58260.

It is an arithmetic number, because the mean of its divisors is an integer number (3499380).

Almost surely, 2^20851079 is an apocalyptic number.

20851079 is a deficient number, since it is larger than the sum of its proper divisors (145201).

20851079 is an frugal number, since it uses more digits than its factorization.

20851079 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 841 (or 600 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 20851079 is about 4566.2981724806. The cubic root of 20851079 is about 275.2387084363.

The spelling of 20851079 in words is "twenty million, eight hundred fifty-one thousand, seventy-nine".