18664442 has 8 divisors (see below), whose sum is σ = 28015956. Its totient is φ = 9325792.

The previous prime is 18664433. The next prime is 18664483. The reversal of 18664442 is 24446681.

It can be written as a sum of positive squares in 2 ways, for example, as 13184161 + 5480281 = 3631^2 + 2341^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×18664442² = 696722790342728, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2318 + ... + 6534.

Almost surely, 2^18664442 is an apocalyptic number.

18664442 is a deficient number, since it is larger than the sum of its proper divisors (9351514).

18664442 is a wasteful number, since it uses less digits than its factorization.

18664442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6432.

The product of its digits is 36864, while the sum is 35.

The square root of 18664442 is about 4320.2363361279. The cubic root of 18664442 is about 265.2599419221.

The spelling of 18664442 in words is "eighteen million, six hundred sixty-four thousand, four hundred forty-two".