21118669 has 16 divisors (see below), whose sum is σ = 25893504. Its totient is φ = 16948800.

The previous prime is 21118663. The next prime is 21118717. The reversal of 21118669 is 96681112.

It is not a de Polignac number, because 21118669 - 2³ = 21118661 is a prime.

It is a super-2 number, since 2×21118669² = 891996360663122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21118661) 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, 79 + ... + 6499.

It is an arithmetic number, because the mean of its divisors is an integer number (1618344).

Almost surely, 2^21118669 is an apocalyptic number.

It is an amenable number.

21118669 is a deficient number, since it is larger than the sum of its proper divisors (4774835).

21118669 is a wasteful number, since it uses less digits than its factorization.

21118669 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6468.

The product of its digits is 5184, while the sum is 34.

The square root of 21118669 is about 4595.5053040988. The cubic root of 21118669 is about 276.4111224034.

The spelling of 21118669 in words is "twenty-one million, one hundred eighteen thousand, six hundred sixty-nine".