691216396 has 24 divisors (see below), whose sum is σ = 1379306880. Its totient is φ = 300256512.

The previous prime is 691216387. The next prime is 691216399. The reversal of 691216396 is 693612196.

It is not an unprimeable number, because it can be changed into a prime (691216399) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 390076 + ... + 391843.

It is an arithmetic number, because the mean of its divisors is an integer number (57471120).

Almost surely, 2^691216396 is an apocalyptic number.

It is an amenable number.

691216396 is a deficient number, since it is larger than the sum of its proper divisors (688090484).

691216396 is a wasteful number, since it uses less digits than its factorization.

691216396 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 781953 (or 781951 counting only the distinct ones).

The product of its digits is 104976, while the sum is 43.

The square root of 691216396 is about 26290.9945798937. The cubic root of 691216396 is about 884.1745507504.

The spelling of 691216396 in words is "six hundred ninety-one million, two hundred sixteen thousand, three hundred ninety-six".