18261894906 has 32 divisors (see below), whose sum is σ = 41981371200. Its totient is φ = 5877390960.

The previous prime is 18261894869. The next prime is 18261894923. The reversal of 18261894906 is 60949816281.

18261894906 is a `hidden beast` number, since 18 + 2 + 61 + 89 + 490 + 6 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5829180 + ... + 5832311.

It is an arithmetic number, because the mean of its divisors is an integer number (1311917850).

Almost surely, 2^18261894906 is an apocalyptic number.

18261894906 is an abundant number, since it is smaller than the sum of its proper divisors (23719476294).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18261894906 is a wasteful number, since it uses less digits than its factorization.

18261894906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11661531 (or 11661525 counting only the distinct ones).

The product of its (nonzero) digits is 1492992, while the sum is 54.

The spelling of 18261894906 in words is "eighteen billion, two hundred sixty-one million, eight hundred ninety-four thousand, nine hundred six".