20976959 has 4 divisors (see below), whose sum is σ = 21105816. Its totient is φ = 20848104.

The previous prime is 20976937. The next prime is 20976973. The reversal of 20976959 is 95967902.

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-20976959 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 (20976359) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64184 + ... + 64509.

It is an arithmetic number, because the mean of its divisors is an integer number (5276454).

Almost surely, 2^20976959 is an apocalyptic number.

20976959 is a deficient number, since it is larger than the sum of its proper divisors (128857).

20976959 is a wasteful number, since it uses less digits than its factorization.

20976959 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 128856.

The product of its (nonzero) digits is 306180, while the sum is 47.

The square root of 20976959 is about 4580.0610257943. The cubic root of 20976959 is about 275.7914785349.

The spelling of 20976959 in words is "twenty million, nine hundred seventy-six thousand, nine hundred fifty-nine".