18679640 has 32 divisors (see below), whose sum is σ = 48034080. Its totient is φ = 6404352.

The previous prime is 18679627. The next prime is 18679643. The reversal of 18679640 is 4697681.

It is a Smith number, since the sum of its digits (41) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18679643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33077 + ... + 33636.

It is an arithmetic number, because the mean of its divisors is an integer number (1501065).

Almost surely, 2^18679640 is an apocalyptic number.

18679640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18679640 is an abundant number, since it is smaller than the sum of its proper divisors (29354440).

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

18679640 is a wasteful number, since it uses less digits than its factorization.

18679640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66731 (or 66727 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 41.

The square root of 18679640 is about 4321.9949097610. The cubic root of 18679640 is about 265.3319206230.

The spelling of 18679640 in words is "eighteen million, six hundred seventy-nine thousand, six hundred forty".