691040671 has 4 divisors (see below), whose sum is σ = 705743712. Its totient is φ = 676337632.

The previous prime is 691040639. The next prime is 691040677. The reversal of 691040671 is 176040196.

691040671 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 691040671 - 2⁵ = 691040639 is a prime.

It is a super-2 number, since 2×691040671² = 955074417952260482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691040677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7351450 + ... + 7351543.

It is an arithmetic number, because the mean of its divisors is an integer number (176435928).

Almost surely, 2^691040671 is an apocalyptic number.

691040671 is a deficient number, since it is larger than the sum of its proper divisors (14703041).

691040671 is a wasteful number, since it uses less digits than its factorization.

691040671 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14703040.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 691040671 is about 26287.6524436854. The cubic root of 691040671 is about 884.0996177568.

The spelling of 691040671 in words is "six hundred ninety-one million, forty thousand, six hundred seventy-one".