690891 has 12 divisors (see below), whose sum is σ = 951096. Its totient is φ = 446080.

The previous prime is 690889. The next prime is 690919. The reversal of 690891 is 198096.

It is a happy number.

690891 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 690891 - 2¹ = 690889 is a prime.

It is not an unprimeable number, because it can be changed into a prime (690841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4975 + ... + 5111.

It is an arithmetic number, because the mean of its divisors is an integer number (79258).

2⁶⁹⁰⁸⁹¹ is an apocalyptic number.

690891 is a deficient number, since it is larger than the sum of its proper divisors (260205).

690891 is a wasteful number, since it uses less digits than its factorization.

690891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222 (or 181 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 33.

The square root of 690891 is about 831.1985322412. The cubic root of 690891 is about 88.4035784742.

The spelling of 690891 in words is "six hundred ninety thousand, eight hundred ninety-one".