18636240 has 80 divisors (see below), whose sum is σ = 66031488. Its totient is φ = 4259328.

The previous prime is 18636229. The next prime is 18636259. The reversal of 18636240 is 4263681.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 18636198 and 18636207.

It is a congruent number.

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, 3867 + ... + 7226.

Almost surely, 2^18636240 is an apocalyptic number.

18636240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18636240 is an abundant number, since it is smaller than the sum of its proper divisors (47395248).

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

18636240 is a wasteful number, since it uses less digits than its factorization.

18636240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11116 (or 11110 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 18636240 is about 4316.9711604318. The cubic root of 18636240 is about 265.1262718502.

The spelling of 18636240 in words is "eighteen million, six hundred thirty-six thousand, two hundred forty".