1881618856 has 16 divisors (see below), whose sum is σ = 3799422900. Its totient is φ = 868439424.

The previous prime is 1881618841. The next prime is 1881618857. The reversal of 1881618856 is 6588161881.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1871946756 + 9672100 = 43266^2 + 3110^2 .

It is a Harshad number since it is a multiple of its sum of digits (52).

It is not an unprimeable number, because it can be changed into a prime (1881618857) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9046141 + ... + 9046348.

Almost surely, 2^1881618856 is an apocalyptic number.

It is an amenable number.

1881618856 is an abundant number, since it is smaller than the sum of its proper divisors (1917804044).

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

1881618856 is a wasteful number, since it uses less digits than its factorization.

1881618856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18092508 (or 18092504 counting only the distinct ones).

The product of its digits is 737280, while the sum is 52.

The square root of 1881618856 is about 43377.6308251154. The cubic root of 1881618856 is about 1234.5553111685. Note that the first 3 decimals are identical.

The spelling of 1881618856 in words is "one billion, eight hundred eighty-one million, six hundred eighteen thousand, eight hundred fifty-six".