691319440629 has 40 divisors (see below), whose sum is σ = 1070936031000. Its totient is φ = 443898620928.

The previous prime is 691319440597. The next prime is 691319440631. The reversal of 691319440629 is 926044913196.

It is a happy number.

691319440629 is a `hidden beast` number, since 6 + 9 + 1 + 3 + 1 + 9 + 4 + 4 + 0 + 629 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 172725022404 + 518594418225 = 415602^2 + 720135^2 .

It is not a de Polignac number, because 691319440629 - 2⁵ = 691319440597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691319440729) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 600957 + ... + 1320525.

It is an arithmetic number, because the mean of its divisors is an integer number (26773400775).

Almost surely, 2^691319440629 is an apocalyptic number.

It is an amenable number.

691319440629 is a deficient number, since it is larger than the sum of its proper divisors (379616590371).

691319440629 is a wasteful number, since it uses less digits than its factorization.

691319440629 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720019 (or 720010 counting only the distinct ones).

The product of its (nonzero) digits is 2519424, while the sum is 54.

The spelling of 691319440629 in words is "six hundred ninety-one billion, three hundred nineteen million, four hundred forty thousand, six hundred twenty-nine".