1861831880 has 16 divisors (see below), whose sum is σ = 4189121820. Its totient is φ = 744732736.

The previous prime is 1861831877. The next prime is 1861831889. The reversal of 1861831880 is 881381681.

It can be written as a sum of positive squares in 2 ways, for example, as 1859161924 + 2669956 = 43118^2 + 1634^2 .

It is not an unprimeable number, because it can be changed into a prime (1861831889) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 23272859 + ... + 23272938.

Almost surely, 2^1861831880 is an apocalyptic number.

1861831880 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1861831880 is an abundant number, since it is smaller than the sum of its proper divisors (2327289940).

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

1861831880 is a wasteful number, since it uses less digits than its factorization.

1861831880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46545808 (or 46545804 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 44.

The square root of 1861831880 is about 43148.9499292856. The cubic root of 1861831880 is about 1230.2125527753.

The spelling of 1861831880 in words is "one billion, eight hundred sixty-one million, eight hundred thirty-one thousand, eight hundred eighty".