18850891 has 4 divisors (see below), whose sum is σ = 19159984. Its totient is φ = 18541800.

The previous prime is 18850879. The next prime is 18850903. The reversal of 18850891 is 19805881.

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

It is an interprime number because it is at equal distance from previous prime (18850879) and next prime (18850903).

It is a cyclic number.

It is not a de Polignac number, because 18850891 - 2¹⁹ = 18326603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18850291) 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 3 ways as a sum of consecutive naturals, for example, 154455 + ... + 154576.

It is an arithmetic number, because the mean of its divisors is an integer number (4789996).

Almost surely, 2^18850891 is an apocalyptic number.

18850891 is a deficient number, since it is larger than the sum of its proper divisors (309093).

18850891 is an equidigital number, since it uses as much as digits as its factorization.

18850891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309092.

The product of its (nonzero) digits is 23040, while the sum is 40.

The square root of 18850891 is about 4341.7612785597. The cubic root of 18850891 is about 266.1402910064.

The spelling of 18850891 in words is "eighteen million, eight hundred fifty thousand, eight hundred ninety-one".