18972040 has 32 divisors (see below), whose sum is σ = 43416000. Its totient is φ = 7459264.

The previous prime is 18972029. The next prime is 18972047. The reversal of 18972040 is 4027981.

It is a junction number, because it is equal to n+sod(n) for n = 18971993 and 18972011.

It is not an unprimeable number, because it can be changed into a prime (18972047) 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, 1660 + ... + 6379.

It is an arithmetic number, because the mean of its divisors is an integer number (1356750).

Almost surely, 2^18972040 is an apocalyptic number.

18972040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18972040 is an abundant number, since it is smaller than the sum of its proper divisors (24443960).

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

18972040 is a wasteful number, since it uses less digits than its factorization.

18972040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8109 (or 8105 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 18972040 is about 4355.6905307884. The cubic root of 18972040 is about 266.7092084906.

The spelling of 18972040 in words is "eighteen million, nine hundred seventy-two thousand, forty".