18981653 has 8 divisors (see below), whose sum is σ = 19290240. Its totient is φ = 18675360.

The previous prime is 18981649. The next prime is 18981661. The reversal of 18981653 is 35618981.

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 18981653 - 2² = 18981649 is a prime.

It is a super-2 number, since 2×18981653² = 720606301224818, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18981653.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18981953) 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, 23726 + ... + 24512.

It is an arithmetic number, because the mean of its divisors is an integer number (2411280).

Almost surely, 2^18981653 is an apocalyptic number.

It is an amenable number.

18981653 is a deficient number, since it is larger than the sum of its proper divisors (308587).

18981653 is an equidigital number, since it uses as much as digits as its factorization.

18981653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147.

The product of its digits is 51840, while the sum is 41.

The square root of 18981653 is about 4356.7938900067. The cubic root of 18981653 is about 266.7542474482.

The spelling of 18981653 in words is "eighteen million, nine hundred eighty-one thousand, six hundred fifty-three".