18930861 has 16 divisors (see below), whose sum is σ = 28209600. Its totient is φ = 12546864.

The previous prime is 18930853. The next prime is 18930887. The reversal of 18930861 is 16803981.

It is not a de Polignac number, because 18930861 - 2³ = 18930853 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18930841) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2875 + ... + 6791.

It is an arithmetic number, because the mean of its divisors is an integer number (1763100).

Almost surely, 2^18930861 is an apocalyptic number.

It is an amenable number.

18930861 is a deficient number, since it is larger than the sum of its proper divisors (9278739).

18930861 is a wasteful number, since it uses less digits than its factorization.

18930861 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4105 (or 4099 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 18930861 is about 4350.9609283467. The cubic root of 18930861 is about 266.5161037218.

It can be divided in two parts, 18930 and 861, that added together give a palindrome (19791).

The spelling of 18930861 in words is "eighteen million, nine hundred thirty thousand, eight hundred sixty-one".