20979377 has 12 divisors (see below), whose sum is σ = 22453980. Its totient is φ = 19597056.

The previous prime is 20979373. The next prime is 20979389. The reversal of 20979377 is 77397902.

It can be written as a sum of positive squares in 6 ways, for example, as 1628176 + 19351201 = 1276^2 + 4399^2 .

It is not a de Polignac number, because 20979377 - 2² = 20979373 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20979373) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 66023 + ... + 66339.

It is an arithmetic number, because the mean of its divisors is an integer number (1871165).

Almost surely, 2^20979377 is an apocalyptic number.

It is an amenable number.

20979377 is a deficient number, since it is larger than the sum of its proper divisors (1474603).

20979377 is a wasteful number, since it uses less digits than its factorization.

20979377 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580 (or 563 counting only the distinct ones).

The product of its (nonzero) digits is 166698, while the sum is 44.

The square root of 20979377 is about 4580.3249884697. The cubic root of 20979377 is about 275.8020748941.

The spelling of 20979377 in words is "twenty million, nine hundred seventy-nine thousand, three hundred seventy-seven".