18690786 has 36 divisors (see below), whose sum is σ = 43030962. Its totient is φ = 5862144.

The previous prime is 18690739. The next prime is 18690797. The reversal of 18690786 is 68709681.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 18020025 + 670761 = 4245^2 + 819^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 3406 + ... + 6998.

Almost surely, 2^18690786 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18690786, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21515481).

18690786 is an abundant number, since it is smaller than the sum of its proper divisors (24340176).

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

18690786 is a wasteful number, since it uses less digits than its factorization.

18690786 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3635 (or 3615 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 45.

The square root of 18690786 is about 4323.2841683146. The cubic root of 18690786 is about 265.3846839804.

The spelling of 18690786 in words is "eighteen million, six hundred ninety thousand, seven hundred eighty-six".