691216404 has 48 divisors (see below), whose sum is σ = 1651335168. Its totient is φ = 224931168.

The previous prime is 691216403. The next prime is 691216439. The reversal of 691216404 is 404612196.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691216403) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 259809 + ... + 262455.

It is an arithmetic number, because the mean of its divisors is an integer number (34402816).

Almost surely, 2^691216404 is an apocalyptic number.

It is an amenable number.

691216404 is an abundant number, since it is smaller than the sum of its proper divisors (960118764).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

691216404 is a wasteful number, since it uses less digits than its factorization.

691216404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3164 (or 3162 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 691216404 is about 26290.9947320371. The cubic root of 691216404 is about 884.1745541615.

The spelling of 691216404 in words is "six hundred ninety-one million, two hundred sixteen thousand, four hundred four".