1660891856 has 40 divisors (see below), whose sum is σ = 3546127200. Its totient is φ = 748734336.

The previous prime is 1660891777. The next prime is 1660891861. The reversal of 1660891856 is 6581980661.

1660891856 = 3524² + 3525² + ... + 3652².

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 83906 + ... + 101793.

It is an arithmetic number, because the mean of its divisors is an integer number (88653180).

Almost surely, 2^1660891856 is an apocalyptic number.

1660891856 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1660891856 is an abundant number, since it is smaller than the sum of its proper divisors (1885235344).

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

1660891856 is a wasteful number, since it uses less digits than its factorization.

1660891856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185763 (or 185757 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 50.

The square root of 1660891856 is about 40754.0409775522. The cubic root of 1660891856 is about 1184.2601578611.

The spelling of 1660891856 in words is "one billion, six hundred sixty million, eight hundred ninety-one thousand, eight hundred fifty-six".