687709440 has 504 divisors, whose sum is σ = 2734528608. Its totient is φ = 164229120.

The previous prime is 687709433. The next prime is 687709459. The reversal of 687709440 is 44907786.

It is a super-2 number, since 2×687709440² = 945888547730227200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 10264287 + ... + 10264353.

It is an arithmetic number, because the mean of its divisors is an integer number (5425652).

Almost surely, 2^687709440 is an apocalyptic number.

687709440 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 687709440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1367264304).

687709440 is an abundant number, since it is smaller than the sum of its proper divisors (2046819168).

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

687709440 is an equidigital number, since it uses as much as digits as its factorization.

687709440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 88 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 45.

The square root of 687709440 is about 26224.2147642213. The cubic root of 687709440 is about 882.6766985085.

It can be divided in two parts, 68770 and 9440, that added together give a triangular number (78210 = T₃₉₅).

The spelling of 687709440 in words is "six hundred eighty-seven million, seven hundred nine thousand, four hundred forty".