18661279 has 8 divisors (see below), whose sum is σ = 22967840. Its totient is φ = 14764896.

The previous prime is 18661277. The next prime is 18661289. The reversal of 18661279 is 97216681.

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

It is a cyclic number.

It is not a de Polignac number, because 18661279 - 2¹ = 18661277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18661271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 102444 + ... + 102625.

It is an arithmetic number, because the mean of its divisors is an integer number (2870980).

Almost surely, 2^18661279 is an apocalyptic number.

18661279 is a deficient number, since it is larger than the sum of its proper divisors (4306561).

18661279 is a wasteful number, since it uses less digits than its factorization.

18661279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 205089.

The product of its digits is 36288, while the sum is 40.

The square root of 18661279 is about 4319.8702526812. The cubic root of 18661279 is about 265.2449568399.

The spelling of 18661279 in words is "eighteen million, six hundred sixty-one thousand, two hundred seventy-nine".