1861766856 has 64 divisors (see below), whose sum is σ = 5235470400. Its totient is φ = 620583120.

The previous prime is 1861766839. The next prime is 1861766873. The reversal of 1861766856 is 6586671681.

1861766856 is a `hidden beast` number, since 18 + 617 + 6 + 6 + 8 + 5 + 6 = 666.

It is an interprime number because it is at equal distance from previous prime (1861766839) and next prime (1861766873).

It is a super-2 number, since 2×1861766856² = 6932351652200249472, which contains 22 as substring.

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

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 35710 + ... + 70701.

It is an arithmetic number, because the mean of its divisors is an integer number (81804225).

Almost surely, 2^1861766856 is an apocalyptic number.

It is an amenable number.

1861766856 is an abundant number, since it is smaller than the sum of its proper divisors (3373703544).

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

1861766856 is an equidigital number, since it uses as much as digits as its factorization.

1861766856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106438 (or 106416 counting only the distinct ones).

The product of its digits is 2903040, while the sum is 54.

The square root of 1861766856 is about 43148.1964397123. The cubic root of 1861766856 is about 1230.1982309894.

The spelling of 1861766856 in words is "one billion, eight hundred sixty-one million, seven hundred sixty-six thousand, eight hundred fifty-six".