18616081 has 8 divisors (see below), whose sum is σ = 20340000. Its totient is φ = 16897440.

The previous prime is 18616063. The next prime is 18616109. The reversal of 18616081 is 18061681.

It is a happy number.

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 18616081 - 2¹³ = 18607889 is a prime.

It is a super-2 number, since 2×18616081² = 693116943597122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18616061) 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, 11670 + ... + 13168.

It is an arithmetic number, because the mean of its divisors is an integer number (2542500).

Almost surely, 2^18616081 is an apocalyptic number.

18616081 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18616081 is a deficient number, since it is larger than the sum of its proper divisors (1723919).

18616081 is a wasteful number, since it uses less digits than its factorization.

18616081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2639.

The product of its (nonzero) digits is 2304, while the sum is 31.

The square root of 18616081 is about 4314.6356740749. The cubic root of 18616081 is about 265.0306408144.

The spelling of 18616081 in words is "eighteen million, six hundred sixteen thousand, eighty-one".