18773664 has 144 divisors (see below), whose sum is σ = 61937568. Its totient is φ = 4935168.

The previous prime is 18773663. The next prime is 18773669. The reversal of 18773664 is 46637781.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (18773663) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 60999 + ... + 61305.

It is an arithmetic number, because the mean of its divisors is an integer number (430122).

Almost surely, 2^18773664 is an apocalyptic number.

18773664 is a gapful number since it is divisible by the number (14) 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 18773664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30968784).

18773664 is an abundant number, since it is smaller than the sum of its proper divisors (43163904).

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

18773664 is a wasteful number, since it uses less digits than its factorization.

18773664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 332 counting only the distinct ones).

The product of its digits is 169344, while the sum is 42.

The square root of 18773664 is about 4332.8586406667. The cubic root of 18773664 is about 265.7763586544.

The spelling of 18773664 in words is "eighteen million, seven hundred seventy-three thousand, six hundred sixty-four".