616161618 has 12 divisors (see below), whose sum is σ = 1335016878. Its totient is φ = 205387200.

The previous prime is 616161613. The next prime is 616161619. The reversal of 616161618 is 816161616.

616161618 is a `hidden beast` number, since 616 + 16 + 16 + 18 = 666.

It can be written as a sum of positive squares in only one way, i.e., 370832049 + 245329569 = 19257^2 + 15663^2 .

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (616161613) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 17115583 + ... + 17115618.

Almost surely, 2^616161618 is an apocalyptic number.

616161618 is an abundant number, since it is smaller than the sum of its proper divisors (718855260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

616161618 is a wasteful number, since it uses less digits than its factorization.

616161618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34231209 (or 34231206 counting only the distinct ones).

The product of its digits is 10368, while the sum is 36.

The square root of 616161618 is about 24822.6029658455. The cubic root of 616161618 is about 850.9385793765.

The spelling of 616161618 in words is "six hundred sixteen million, one hundred sixty-one thousand, six hundred eighteen".