688270440 has 256 divisors, whose sum is σ = 2554675200. Its totient is φ = 145843200.

The previous prime is 688270439. The next prime is 688270447. The reversal of 688270440 is 44072886.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (688270447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 324985 + ... + 327095.

It is an arithmetic number, because the mean of its divisors is an integer number (9979200).

Almost surely, 2^688270440 is an apocalyptic number.

688270440 is a gapful number since it is divisible by the number (60) 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 688270440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1277337600).

688270440 is an abundant number, since it is smaller than the sum of its proper divisors (1866404760).

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

688270440 is a wasteful number, since it uses less digits than its factorization.

688270440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2168 (or 2164 counting only the distinct ones).

The product of its (nonzero) digits is 86016, while the sum is 39.

The square root of 688270440 is about 26234.9088048729. The cubic root of 688270440 is about 882.9166482177.

The spelling of 688270440 in words is "six hundred eighty-eight million, two hundred seventy thousand, four hundred forty".