18220869 has 24 divisors (see below), whose sum is σ = 27518400. Its totient is φ = 12047616.

The previous prime is 18220861. The next prime is 18220871. The reversal of 18220869 is 96802281.

It is not a de Polignac number, because 18220869 - 2³ = 18220861 is a prime.

It is a super-2 number, since 2×18220869² = 664000134230322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18220861) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40357 + ... + 40805.

It is an arithmetic number, because the mean of its divisors is an integer number (1146600).

Almost surely, 2^18220869 is an apocalyptic number.

It is an amenable number.

18220869 is a deficient number, since it is larger than the sum of its proper divisors (9297531).

18220869 is an equidigital number, since it uses as much as digits as its factorization.

18220869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 631 (or 619 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 36.

The square root of 18220869 is about 4268.5909853253. The cubic root of 18220869 is about 263.1417116161.

The spelling of 18220869 in words is "eighteen million, two hundred twenty thousand, eight hundred sixty-nine".