18156672 has 48 divisors (see below), whose sum is σ = 52251030. Its totient is φ = 6051840.

The previous prime is 18156661. The next prime is 18156673. The reversal of 18156672 is 27665181.

It can be written as a sum of positive squares in only one way, i.e., 14561856 + 3594816 = 3816^2 + 1896^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (18156673) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6729 + ... + 9032.

Almost surely, 2^18156672 is an apocalyptic number.

18156672 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

18156672 is an abundant number, since it is smaller than the sum of its proper divisors (34094358).

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

18156672 is a wasteful number, since it uses less digits than its factorization.

18156672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15781 (or 15766 counting only the distinct ones).

The product of its digits is 20160, while the sum is 36.

The square root of 18156672 is about 4261.0646556935. The cubic root of 18156672 is about 262.8323083928.

The spelling of 18156672 in words is "eighteen million, one hundred fifty-six thousand, six hundred seventy-two".