18903393 has 6 divisors (see below), whose sum is σ = 27304914. Its totient is φ = 12602256.

The previous prime is 18903377. The next prime is 18903407. The reversal of 18903393 is 39330981.

It can be written as a sum of positive squares in only one way, i.e., 14379264 + 4524129 = 3792^2 + 2127^2 .

It is not a de Polignac number, because 18903393 - 2⁴ = 18903377 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18903323) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1050180 + ... + 1050197.

It is an arithmetic number, because the mean of its divisors is an integer number (4550819).

Almost surely, 2^18903393 is an apocalyptic number.

It is an amenable number.

18903393 is a deficient number, since it is larger than the sum of its proper divisors (8401521).

18903393 is a wasteful number, since it uses less digits than its factorization.

18903393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2100383 (or 2100380 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 18903393 is about 4347.8032384182. The cubic root of 18903393 is about 266.3871395599.

The spelling of 18903393 in words is "eighteen million, nine hundred three thousand, three hundred ninety-three".