18387344 has 10 divisors (see below), whose sum is σ = 35625510. Its totient is φ = 9193664.

The previous prime is 18387331. The next prime is 18387349. The reversal of 18387344 is 44378381.

It can be written as a sum of positive squares in only one way, i.e., 18386944 + 400 = 4288^2 + 20^2 .

It is a junction number, because it is equal to n+sod(n) for n = 18387298 and 18387307.

It is not an unprimeable number, because it can be changed into a prime (18387349) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 574589 + ... + 574620.

It is an arithmetic number, because the mean of its divisors is an integer number (3562551).

Almost surely, 2^18387344 is an apocalyptic number.

It is an amenable number.

18387344 is a deficient number, since it is larger than the sum of its proper divisors (17238166).

18387344 is a wasteful number, since it uses less digits than its factorization.

18387344 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1149217 (or 1149211 counting only the distinct ones).

The product of its digits is 64512, while the sum is 38.

The square root of 18387344 is about 4288.0466415374. The cubic root of 18387344 is about 263.9406814997.

The spelling of 18387344 in words is "eighteen million, three hundred eighty-seven thousand, three hundred forty-four".