18012557 has 4 divisors (see below), whose sum is σ = 18079296. Its totient is φ = 17945820.

The previous prime is 18012541. The next prime is 18012559. The reversal of 18012557 is 75521081.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 18012557 - 2⁴ = 18012541 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 (18012559) 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, 32963 + ... + 33504.

It is an arithmetic number, because the mean of its divisors is an integer number (4519824).

Almost surely, 2^18012557 is an apocalyptic number.

It is an amenable number.

18012557 is a deficient number, since it is larger than the sum of its proper divisors (66739).

18012557 is an equidigital number, since it uses as much as digits as its factorization.

18012557 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66738.

The product of its (nonzero) digits is 2800, while the sum is 29.

The square root of 18012557 is about 4244.1202857601. The cubic root of 18012557 is about 262.1350671990.

The spelling of 18012557 in words is "eighteen million, twelve thousand, five hundred fifty-seven".