1680357747281 has 2 divisors, whose sum is σ = 1680357747282. Its totient is φ = 1680357747280.

The previous prime is 1680357747269. The next prime is 1680357747301. The reversal of 1680357747281 is 1827477530861.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1063125966400 + 617231780881 = 1031080^2 + 785641^2 .

It is a cyclic number.

It is not a de Polignac number, because 1680357747281 - 2⁶ = 1680357747217 is a prime.

It is a super-2 number, since 2×1680357747281² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1680357747281.

It is not a weakly prime, because it can be changed into another prime (1680357749281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 840178873640 + 840178873641.

It is an arithmetic number, because the mean of its divisors is an integer number (840178873641).

Almost surely, 2^{1680357747281} is an apocalyptic number.

It is an amenable number.

1680357747281 is a deficient number, since it is larger than the sum of its proper divisors (1).

1680357747281 is an equidigital number, since it uses as much as digits as its factorization.

1680357747281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15805440, while the sum is 59.

The spelling of 1680357747281 in words is "one trillion, six hundred eighty billion, three hundred fifty-seven million, seven hundred forty-seven thousand, two hundred eighty-one".