691634 has 4 divisors (see below), whose sum is σ = 1037454. Its totient is φ = 345816.

The previous prime is 691631. The next prime is 691637. The reversal of 691634 is 436196.

691634 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 an interprime number because it is at equal distance from previous prime (691631) and next prime (691637).

It can be written as a sum of positive squares in only one way, i.e., 426409 + 265225 = 653^2 + 515^2 .

It is a junction number, because it is equal to n+sod(n) for n = 691597 and 691606.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 691634.

It is not an unprimeable number, because it can be changed into a prime (691631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172907 + ... + 172910.

2⁶⁹¹⁶³⁴ is an apocalyptic number.

691634 is a deficient number, since it is larger than the sum of its proper divisors (345820).

691634 is a wasteful number, since it uses less digits than its factorization.

691634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345819.

The product of its digits is 3888, while the sum is 29.

The square root of 691634 is about 831.6453571084. The cubic root of 691634 is about 88.4352575316.

The spelling of 691634 in words is "six hundred ninety-one thousand, six hundred thirty-four".