18850861 has 4 divisors (see below), whose sum is σ = 18866592. Its totient is φ = 18835132.

The previous prime is 18850849. The next prime is 18850873. The reversal of 18850861 is 16805881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 16805881 = 37 ⋅454213.

It is an interprime number because it is at equal distance from previous prime (18850849) and next prime (18850873).

It is a cyclic number.

It is not a de Polignac number, because 18850861 - 2⁵ = 18850829 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18850861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18850061) 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, 5905 + ... + 8518.

It is an arithmetic number, because the mean of its divisors is an integer number (4716648).

Almost surely, 2^18850861 is an apocalyptic number.

It is an amenable number.

18850861 is a deficient number, since it is larger than the sum of its proper divisors (15731).

18850861 is a wasteful number, since it uses less digits than its factorization.

18850861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15730.

The product of its (nonzero) digits is 15360, while the sum is 37.

The square root of 18850861 is about 4341.7578237391. The cubic root of 18850861 is about 266.1401498245.

The spelling of 18850861 in words is "eighteen million, eight hundred fifty thousand, eight hundred sixty-one".