691602031 has 2 divisors, whose sum is σ = 691602032. Its totient is φ = 691602030.

The previous prime is 691602029. The next prime is 691602061. The reversal of 691602031 is 130206196.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 691602031 - 2¹ = 691602029 is a prime.

It is a super-2 number, since 2×691602031² = 956626738566649922, which contains 22 as substring.

Together with 691602029, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691602061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345801015 + 345801016.

It is an arithmetic number, because the mean of its divisors is an integer number (345801016).

Almost surely, 2^691602031 is an apocalyptic number.

691602031 is a deficient number, since it is larger than the sum of its proper divisors (1).

691602031 is an equidigital number, since it uses as much as digits as its factorization.

691602031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 691602031 is about 26298.3275323736. The cubic root of 691602031 is about 884.3389494659.

The spelling of 691602031 in words is "six hundred ninety-one million, six hundred two thousand, thirty-one".