1861708840 has 16 divisors (see below), whose sum is σ = 4188844980. Its totient is φ = 744683520.

The previous prime is 1861708831. The next prime is 1861708843. The reversal of 1861708840 is 488071681.

It can be written as a sum of positive squares in 2 ways, for example, as 1845046116 + 16662724 = 42954^2 + 4082^2 .

It is not an unprimeable number, because it can be changed into a prime (1861708843) 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, 23271321 + ... + 23271400.

Almost surely, 2^1861708840 is an apocalyptic number.

1861708840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1861708840 is an abundant number, since it is smaller than the sum of its proper divisors (2327136140).

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

1861708840 is a wasteful number, since it uses less digits than its factorization.

1861708840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46542732 (or 46542728 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 43.

The square root of 1861708840 is about 43147.5241468152. The cubic root of 1861708840 is about 1230.1854524610.

The spelling of 1861708840 in words is "one billion, eight hundred sixty-one million, seven hundred eight thousand, eight hundred forty".