18258881 has 8 divisors (see below), whose sum is σ = 18532584. Its totient is φ = 17987200.

The previous prime is 18258869. The next prime is 18258887. The reversal of 18258881 is 18885281.

It can be written as a sum of positive squares in 4 ways, for example, as 6760000 + 11498881 = 2600^2 + 3391^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 18258881 - 2²² = 14064577 is a prime.

It is a super-2 number, since 2×18258881² = 666773470744322, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (18258887) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 29285 + ... + 29901.

It is an arithmetic number, because the mean of its divisors is an integer number (2316573).

Almost surely, 2^18258881 is an apocalyptic number.

It is an amenable number.

18258881 is a deficient number, since it is larger than the sum of its proper divisors (273703).

18258881 is a wasteful number, since it uses less digits than its factorization.

18258881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1011.

The product of its digits is 40960, while the sum is 41.

The square root of 18258881 is about 4273.0411886618. The cubic root of 18258881 is about 263.3245714473.

The spelling of 18258881 in words is "eighteen million, two hundred fifty-eight thousand, eight hundred eighty-one".