20974669 has 4 divisors (see below), whose sum is σ = 21462496. Its totient is φ = 20486844.

The previous prime is 20974663. The next prime is 20974687. The reversal of 20974669 is 96647902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20974669 - 2⁵ = 20974637 is a prime.

It is a super-2 number, since 2×20974669² = 879873479319122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (43), and also a Moran number because the ratio is a prime number: 487783 = 20974669 / (2 + 0 + 9 + 7 + 4 + 6 + 6 + 9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20974663) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243849 + ... + 243934.

It is an arithmetic number, because the mean of its divisors is an integer number (5365624).

Almost surely, 2^20974669 is an apocalyptic number.

It is an amenable number.

20974669 is a deficient number, since it is larger than the sum of its proper divisors (487827).

20974669 is an equidigital number, since it uses as much as digits as its factorization.

20974669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 487826.

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 20974669 is about 4579.8110223021. The cubic root of 20974669 is about 275.7814423572.

The spelling of 20974669 in words is "twenty million, nine hundred seventy-four thousand, six hundred sixty-nine".