687133440 has 216 divisors, whose sum is σ = 2717359008. Its totient is φ = 157040640.

The previous prime is 687133429. The next prime is 687133471. The reversal of 687133440 is 44331786.

687133440 is a `hidden beast` number, since 6 + 87 + 133 + 440 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 687133395 and 687133404.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 76380 + ... + 84900.

Almost surely, 2^687133440 is an apocalyptic number.

687133440 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 687133440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1358679504).

687133440 is an abundant number, since it is smaller than the sum of its proper divisors (2030225568).

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

687133440 is a wasteful number, since it uses less digits than its factorization.

687133440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8555 (or 8538 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 36.

The square root of 687133440 is about 26213.2302473388. The cubic root of 687133440 is about 882.4301972198.

The spelling of 687133440 in words is "six hundred eighty-seven million, one hundred thirty-three thousand, four hundred forty".