18396631 has 4 divisors (see below), whose sum is σ = 20069064. Its totient is φ = 16724200.

The previous prime is 18396629. The next prime is 18396661. The reversal of 18396631 is 13669381.

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

It is a cyclic number.

It is not a de Polignac number, because 18396631 - 2¹ = 18396629 is a prime.

It is a super-2 number, since 2×18396631² = 676872064300322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18396661) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 836200 + ... + 836221.

It is an arithmetic number, because the mean of its divisors is an integer number (5017266).

Almost surely, 2^18396631 is an apocalyptic number.

18396631 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18396631 is a deficient number, since it is larger than the sum of its proper divisors (1672433).

18396631 is a wasteful number, since it uses less digits than its factorization.

18396631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1672432.

The product of its digits is 23328, while the sum is 37.

The square root of 18396631 is about 4289.1293988407. The cubic root of 18396631 is about 263.9851106923.

The spelling of 18396631 in words is "eighteen million, three hundred ninety-six thousand, six hundred thirty-one".