20279917 has 4 divisors (see below), whose sum is σ = 23177056. Its totient is φ = 17382780.

The previous prime is 20279899. The next prime is 20279923. The reversal of 20279917 is 71997202.

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 20279917 - 2¹¹ = 20277869 is a prime.

It is a super-2 number, since 2×20279917² = 822550067053778, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20279927) 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, 1448559 + ... + 1448572.

It is an arithmetic number, because the mean of its divisors is an integer number (5794264).

Almost surely, 2^20279917 is an apocalyptic number.

It is an amenable number.

20279917 is a deficient number, since it is larger than the sum of its proper divisors (2897139).

20279917 is an equidigital number, since it uses as much as digits as its factorization.

20279917 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2897138.

The product of its (nonzero) digits is 15876, while the sum is 37.

The square root of 20279917 is about 4503.3228842711. The cubic root of 20279917 is about 272.7022520043.

The spelling of 20279917 in words is "twenty million, two hundred seventy-nine thousand, nine hundred seventeen".