691213 has 4 divisors (see below), whose sum is σ = 695520. Its totient is φ = 686908.

The previous prime is 691199. The next prime is 691231. The reversal of 691213 is 312196.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 691213 - 2⁵ = 691181 is a prime.

It is a super-2 number, since 2×691213² = 955550822738, 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 (691813) 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, 1903 + ... + 2236.

It is an arithmetic number, because the mean of its divisors is an integer number (173880).

2⁶⁹¹²¹³ is an apocalyptic number.

It is an amenable number.

691213 is a deficient number, since it is larger than the sum of its proper divisors (4307).

691213 is a wasteful number, since it uses less digits than its factorization.

691213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4306.

The product of its digits is 324, while the sum is 22.

The square root of 691213 is about 831.3922058812. The cubic root of 691213 is about 88.4173102742.

It can be divided in two parts, 6 and 91213, that added together give a palindrome (91219).

The spelling of 691213 in words is "six hundred ninety-one thousand, two hundred thirteen".