709750721681 has 2 divisors, whose sum is σ = 709750721682. Its totient is φ = 709750721680.

The previous prime is 709750721629. The next prime is 709750721689. The reversal of 709750721681 is 186127057907.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 702384791056 + 7365930625 = 838084^2 + 85825^2 .

It is a cyclic number.

It is not a de Polignac number, because 709750721681 - 2²² = 709746527377 is a prime.

It is a super-2 number, since 2×709750721681² (a number of 25 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (709750721689) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 354875360840 + 354875360841.

It is an arithmetic number, because the mean of its divisors is an integer number (354875360841).

Almost surely, 2^709750721681 is an apocalyptic number.

It is an amenable number.

709750721681 is a deficient number, since it is larger than the sum of its proper divisors (1).

709750721681 is an equidigital number, since it uses as much as digits as its factorization.

709750721681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1481760, while the sum is 53.

The spelling of 709750721681 in words is "seven hundred nine billion, seven hundred fifty million, seven hundred twenty-one thousand, six hundred eighty-one".