20670997 has 16 divisors (see below), whose sum is σ = 23639040. Its totient is φ = 17957632.

The previous prime is 20670989. The next prime is 20671019. The reversal of 20670997 is 79907602.

It is a cyclic number.

It is not a de Polignac number, because 20670997 - 2³ = 20670989 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 (20670197) 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, 10428 + ... + 12250.

It is an arithmetic number, because the mean of its divisors is an integer number (1477440).

Almost surely, 2^20670997 is an apocalyptic number.

It is an amenable number.

20670997 is a deficient number, since it is larger than the sum of its proper divisors (2968043).

20670997 is a wasteful number, since it uses less digits than its factorization.

20670997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1892.

The product of its (nonzero) digits is 47628, while the sum is 40.

The square root of 20670997 is about 4546.5368138837. The cubic root of 20670997 is about 274.4440426391. Note that the first 3 decimals are identical.

The spelling of 20670997 in words is "twenty million, six hundred seventy thousand, nine hundred ninety-seven".