691868448 has 144 divisors (see below), whose sum is σ = 2095250976. Its totient is φ = 215808000.

The previous prime is 691868423. The next prime is 691868449. The reversal of 691868448 is 844868196.

It is a tau number, because it is divible by the number of its divisors (144).

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

It is a junction number, because it is equal to n+sod(n) for n = 691868394 and 691868403.

It is not an unprimeable number, because it can be changed into a prime (691868449) 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, 1228615 + ... + 1229177.

It is an arithmetic number, because the mean of its divisors is an integer number (14550354).

Almost surely, 2^691868448 is an apocalyptic number.

691868448 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 691868448, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1047625488).

691868448 is an abundant number, since it is smaller than the sum of its proper divisors (1403382528).

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

691868448 is a wasteful number, since it uses less digits than its factorization.

691868448 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847 (or 836 counting only the distinct ones).

The product of its digits is 2654208, while the sum is 54.

The square root of 691868448 is about 26303.3923287473. The cubic root of 691868448 is about 884.4524890802.

The spelling of 691868448 in words is "six hundred ninety-one million, eight hundred sixty-eight thousand, four hundred forty-eight".