18868413561 has 16 divisors (see below), whose sum is σ = 26267020416. Its totient is φ = 12025012736.

The previous prime is 18868413541. The next prime is 18868413589. The reversal of 18868413561 is 16531486881.

It is a cyclic number.

It is not a de Polignac number, because 18868413561 - 2²¹ = 18866316409 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18868413541) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 40681 + ... + 198473.

It is an arithmetic number, because the mean of its divisors is an integer number (1641688776).

Almost surely, 2^18868413561 is an apocalyptic number.

It is an amenable number.

18868413561 is a deficient number, since it is larger than the sum of its proper divisors (7398606855).

18868413561 is a wasteful number, since it uses less digits than its factorization.

18868413561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159552.

The product of its digits is 1105920, while the sum is 51.

The spelling of 18868413561 in words is "eighteen billion, eight hundred sixty-eight million, four hundred thirteen thousand, five hundred sixty-one".