18012293 has 4 divisors (see below), whose sum is σ = 19397868. Its totient is φ = 16626720.

The previous prime is 18012259. The next prime is 18012307. The reversal of 18012293 is 39221081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 39221081 = 859 ⋅45659.

It can be written as a sum of positive squares in 2 ways, for example, as 6061444 + 11950849 = 2462^2 + 3457^2 .

It is a cyclic number.

It is not a de Polignac number, because 18012293 - 2¹² = 18008197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18012193) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 692768 + ... + 692793.

It is an arithmetic number, because the mean of its divisors is an integer number (4849467).

Almost surely, 2^18012293 is an apocalyptic number.

18012293 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

18012293 is a deficient number, since it is larger than the sum of its proper divisors (1385575).

18012293 is a wasteful number, since it uses less digits than its factorization.

18012293 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1385574.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 18012293 is about 4244.0891837943. The cubic root of 18012293 is about 262.1337865369.

The spelling of 18012293 in words is "eighteen million, twelve thousand, two hundred ninety-three".