1680926881 has 2 divisors, whose sum is σ = 1680926882. Its totient is φ = 1680926880.

The previous prime is 1680926839. The next prime is 1680926953. The reversal of 1680926881 is 1886290861.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1109955856 + 570971025 = 33316^2 + 23895^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1680926881 is a prime.

It is a super-2 number, since 2×1680926881² = 5651030358536776322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1680926831) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840463440 + 840463441.

It is an arithmetic number, because the mean of its divisors is an integer number (840463441).

Almost surely, 2^1680926881 is an apocalyptic number.

It is an amenable number.

1680926881 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680926881 is an equidigital number, since it uses as much as digits as its factorization.

1680926881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 331776, while the sum is 49.

The square root of 1680926881 is about 40999.1082951813. The cubic root of 1680926881 is about 1189.0029737052.

The spelling of 1680926881 in words is "one billion, six hundred eighty million, nine hundred twenty-six thousand, eight hundred eighty-one".