18213723 has 48 divisors (see below), whose sum is σ = 31599360. Its totient is φ = 9979200.

The previous prime is 18213707. The next prime is 18213733. The reversal of 18213723 is 32731281.

It is not a de Polignac number, because 18213723 - 2⁴ = 18213707 is a prime.

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (18213703) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 43053 + ... + 43473.

It is an arithmetic number, because the mean of its divisors is an integer number (658320).

Almost surely, 2^18213723 is an apocalyptic number.

18213723 is a deficient number, since it is larger than the sum of its proper divisors (13385637).

18213723 is a wasteful number, since it uses less digits than its factorization.

18213723 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 480 (or 477 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 18213723 is about 4267.7538588817. The cubic root of 18213723 is about 263.1073068071.

The spelling of 18213723 in words is "eighteen million, two hundred thirteen thousand, seven hundred twenty-three".