687405990 has 32 divisors (see below), whose sum is σ = 1650725856. Its totient is φ = 183202560.

The previous prime is 687405989. The next prime is 687406009. The reversal of 687405990 is 99504786.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 56010 + ... + 67170.

It is an arithmetic number, because the mean of its divisors is an integer number (51585183).

Almost surely, 2^687405990 is an apocalyptic number.

687405990 is an abundant number, since it is smaller than the sum of its proper divisors (963319866).

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

687405990 is a wasteful number, since it uses less digits than its factorization.

687405990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13224.

The product of its (nonzero) digits is 544320, while the sum is 48.

The square root of 687405990 is about 26218.4284426050. The cubic root of 687405990 is about 882.5468531435.

The spelling of 687405990 in words is "six hundred eighty-seven million, four hundred five thousand, nine hundred ninety".