691198144 has 56 divisors (see below), whose sum is σ = 1688132768. Its totient is φ = 273438720.

The previous prime is 691198117. The next prime is 691198153. The reversal of 691198144 is 441891196.

It is a tau number, because it is divible by the number of its divisors (56).

It is a self number, because there is not a number n which added to its sum of digits gives 691198144.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53517 + ... + 65164.

It is an arithmetic number, because the mean of its divisors is an integer number (30145228).

Almost surely, 2^691198144 is an apocalyptic number.

691198144 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

691198144 is an abundant number, since it is smaller than the sum of its proper divisors (996934624).

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

691198144 is a wasteful number, since it uses less digits than its factorization.

691198144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118713 (or 118703 counting only the distinct ones).

The product of its digits is 62208, while the sum is 43.

The square root of 691198144 is about 26290.6474625484. The cubic root of 691198144 is about 884.1667682884.

The spelling of 691198144 in words is "six hundred ninety-one million, one hundred ninety-eight thousand, one hundred forty-four".