691756923941 has 2 divisors, whose sum is σ = 691756923942. Its totient is φ = 691756923940.

The previous prime is 691756923929. The next prime is 691756924013. The reversal of 691756923941 is 149329657196.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 386329374916 + 305427549025 = 621554^2 + 552655^2 .

It is a cyclic number.

It is not a de Polignac number, because 691756923941 - 2¹⁴ = 691756907557 is a prime.

It is a super-4 number, since 4×691756923941⁴ (a number of 48 digits) contains 4444 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691756923041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345878461970 + 345878461971.

It is an arithmetic number, because the mean of its divisors is an integer number (345878461971).

Almost surely, 2^691756923941 is an apocalyptic number.

It is an amenable number.

691756923941 is a deficient number, since it is larger than the sum of its proper divisors (1).

691756923941 is an equidigital number, since it uses as much as digits as its factorization.

691756923941 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 22044960, while the sum is 62.

The spelling of 691756923941 in words is "six hundred ninety-one billion, seven hundred fifty-six million, nine hundred twenty-three thousand, nine hundred forty-one".