691998912 has 168 divisors, whose sum is σ = 2181301200. Its totient is φ = 208005120.

The previous prime is 691998911. The next prime is 691998913. The reversal of 691998912 is 219899196.

It is an interprime number because it is at equal distance from previous prime (691998911) and next prime (691998913).

It is a nude number because it is divisible by every one of its digits.

It is not an unprimeable number, because it can be changed into a prime (691998911) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 943698 + ... + 944430.

Almost surely, 2^691998912 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691998912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1090650600).

691998912 is an abundant number, since it is smaller than the sum of its proper divisors (1489302288).

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

691998912 is a wasteful number, since it uses less digits than its factorization.

691998912 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 911 (or 898 counting only the distinct ones).

The product of its digits is 629856, while the sum is 54.

The square root of 691998912 is about 26305.8721961466. The cubic root of 691998912 is about 884.5080786256.

The spelling of 691998912 in words is "six hundred ninety-one million, nine hundred ninety-eight thousand, nine hundred twelve".