687920688 has 400 divisors, whose sum is σ = 2587889920. Its totient is φ = 171320832.

The previous prime is 687920677. The next prime is 687920711. The reversal of 687920688 is 886029786.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 2240631 + ... + 2240937.

Almost surely, 2^687920688 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 687920688, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1293944960).

687920688 is an abundant number, since it is smaller than the sum of its proper divisors (1899969232).

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

687920688 is a wasteful number, since it uses less digits than its factorization.

687920688 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366 (or 351 counting only the distinct ones).

The product of its (nonzero) digits is 2322432, while the sum is 54.

The square root of 687920688 is about 26228.2421828074. The cubic root of 687920688 is about 882.7670683591.

The spelling of 687920688 in words is "six hundred eighty-seven million, nine hundred twenty thousand, six hundred eighty-eight".