1816887618 has 128 divisors (see below), whose sum is σ = 5129994240. Its totient is φ = 463682880.

The previous prime is 1816887617. The next prime is 1816887629. The reversal of 1816887618 is 8167886181.

1816887618 is a `hidden beast` number, since 1 + 8 + 16 + 8 + 8 + 7 + 618 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (1816887617) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 146371 + ... + 158297.

It is an arithmetic number, because the mean of its divisors is an integer number (40078080).

Almost surely, 2^1816887618 is an apocalyptic number.

1816887618 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1816887618, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2564997120).

1816887618 is an abundant number, since it is smaller than the sum of its proper divisors (3313106622).

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

1816887618 is a wasteful number, since it uses less digits than its factorization.

1816887618 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11989 (or 11983 counting only the distinct ones).

The product of its digits is 1032192, while the sum is 54.

The square root of 1816887618 is about 42624.9647272581. The cubic root of 1816887618 is about 1220.2327823302.

The spelling of 1816887618 in words is "one billion, eight hundred sixteen million, eight hundred eighty-seven thousand, six hundred eighteen".