691411481 has 2 divisors, whose sum is σ = 691411482. Its totient is φ = 691411480.

The previous prime is 691411477. The next prime is 691411531. The reversal of 691411481 is 184114196.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 688800025 + 2611456 = 26245^2 + 1616^2 .

It is a cyclic number.

It is not a de Polignac number, because 691411481 - 2² = 691411477 is a prime.

It is a super-2 number, since 2×691411481² = 956099672117226722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (691411411) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345705740 + 345705741.

It is an arithmetic number, because the mean of its divisors is an integer number (345705741).

Almost surely, 2^691411481 is an apocalyptic number.

It is an amenable number.

691411481 is a deficient number, since it is larger than the sum of its proper divisors (1).

691411481 is an equidigital number, since it uses as much as digits as its factorization.

691411481 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6912, while the sum is 35.

The square root of 691411481 is about 26294.7044288389. The cubic root of 691411481 is about 884.2577243983.

The spelling of 691411481 in words is "six hundred ninety-one million, four hundred eleven thousand, four hundred eighty-one".