691081634 has 8 divisors (see below), whose sum is σ = 1064639388. Its totient is φ = 336201840.

The previous prime is 691081613. The next prime is 691081639. The reversal of 691081634 is 436180196.

It can be written as a sum of positive squares in 2 ways, for example, as 683979409 + 7102225 = 26153^2 + 2665^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (691081639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4669397 + ... + 4669544.

Almost surely, 2^691081634 is an apocalyptic number.

691081634 is a deficient number, since it is larger than the sum of its proper divisors (373557754).

691081634 is a wasteful number, since it uses less digits than its factorization.

691081634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9338980.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 691081634 is about 26288.4315621910. The cubic root of 691081634 is about 884.1170864137.

The spelling of 691081634 in words is "six hundred ninety-one million, eighty-one thousand, six hundred thirty-four".