20979167 has 16 divisors (see below), whose sum is σ = 23665824. Its totient is φ = 18432000.

The previous prime is 20979137. The next prime is 20979187. The reversal of 20979167 is 76197902.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20979167 - 2¹⁴ = 20962783 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (41).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20979137) 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 15 ways as a sum of consecutive naturals, for example, 81503 + ... + 81759.

It is an arithmetic number, because the mean of its divisors is an integer number (1479114).

Almost surely, 2^20979167 is an apocalyptic number.

20979167 is a deficient number, since it is larger than the sum of its proper divisors (2686657).

20979167 is a wasteful number, since it uses less digits than its factorization.

20979167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 490.

The product of its (nonzero) digits is 47628, while the sum is 41.

The square root of 20979167 is about 4580.3020642748. The cubic root of 20979167 is about 275.8011546470.

The spelling of 20979167 in words is "twenty million, nine hundred seventy-nine thousand, one hundred sixty-seven".