1680591402 has 128 divisors (see below), whose sum is σ = 4364236800. Its totient is φ = 475366320.

The previous prime is 1680591391. The next prime is 1680591427. The reversal of 1680591402 is 2041950861.

1680591402 is a `hidden beast` number, since 1 + 68 + 0 + 591 + 4 + 0 + 2 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4010749 + ... + 4011167.

It is an arithmetic number, because the mean of its divisors is an integer number (34095600).

Almost surely, 2^1680591402 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1680591402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2182118400).

1680591402 is an abundant number, since it is smaller than the sum of its proper divisors (2683645398).

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

1680591402 is an equidigital number, since it uses as much as digits as its factorization.

1680591402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580 (or 562 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 36.

The square root of 1680591402 is about 40995.0167947276. The cubic root of 1680591402 is about 1188.9238681291.

The spelling of 1680591402 in words is "one billion, six hundred eighty million, five hundred ninety-one thousand, four hundred two".