18139924 has 24 divisors (see below), whose sum is σ = 34963488. Its totient is φ = 8166240.

The previous prime is 18139921. The next prime is 18139931. The reversal of 18139924 is 42993181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18139921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2782 + ... + 6634.

It is an arithmetic number, because the mean of its divisors is an integer number (1456812).

Almost surely, 2^18139924 is an apocalyptic number.

It is an amenable number.

18139924 is a deficient number, since it is larger than the sum of its proper divisors (16823564).

18139924 is a wasteful number, since it uses less digits than its factorization.

18139924 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3975 (or 3973 counting only the distinct ones).

The product of its digits is 15552, while the sum is 37.

The square root of 18139924 is about 4259.0989657438. The cubic root of 18139924 is about 262.7514699796.

The spelling of 18139924 in words is "eighteen million, one hundred thirty-nine thousand, nine hundred twenty-four".