18693720 has 128 divisors (see below), whose sum is σ = 65664000. Its totient is φ = 4717440.

The previous prime is 18693709. The next prime is 18693721. The reversal of 18693720 is 2739681.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18693721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 20065 + ... + 20975.

It is an arithmetic number, because the mean of its divisors is an integer number (513000).

Almost surely, 2^18693720 is an apocalyptic number.

18693720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 18693720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32832000).

18693720 is an abundant number, since it is smaller than the sum of its proper divisors (46970280).

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

18693720 is a wasteful number, since it uses less digits than its factorization.

18693720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 950 (or 940 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 18693720 is about 4323.6234803692. The cubic root of 18693720 is about 265.3985695731.

The spelling of 18693720 in words is "eighteen million, six hundred ninety-three thousand, seven hundred twenty".