18871051 has 4 divisors (see below), whose sum is σ = 18909072. Its totient is φ = 18833032.

The previous prime is 18871031. The next prime is 18871067. The reversal of 18871051 is 15017881.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18871051 - 2¹¹ = 18869003 is a prime.

It is a super-2 number, since 2×18871051² = 712233131689202, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18871031) 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, 18256 + ... + 19261.

It is an arithmetic number, because the mean of its divisors is an integer number (4727268).

Almost surely, 2^18871051 is an apocalyptic number.

18871051 is a deficient number, since it is larger than the sum of its proper divisors (38021).

18871051 is an equidigital number, since it uses as much as digits as its factorization.

18871051 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38020.

The product of its (nonzero) digits is 2240, while the sum is 31.

The square root of 18871051 is about 4344.0822966422. The cubic root of 18871051 is about 266.2351313818.

The spelling of 18871051 in words is "eighteen million, eight hundred seventy-one thousand, fifty-one".