687923990 has 16 divisors (see below), whose sum is σ = 1333514448. Its totient is φ = 254002656.

The previous prime is 687923981. The next prime is 687924031. The reversal of 687923990 is 99329786.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 2645732 + ... + 2645991.

It is an arithmetic number, because the mean of its divisors is an integer number (83344653).

Almost surely, 2^687923990 is an apocalyptic number.

687923990 is a deficient number, since it is larger than the sum of its proper divisors (645590458).

687923990 is a wasteful number, since it uses less digits than its factorization.

687923990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5291743.

The product of its (nonzero) digits is 1469664, while the sum is 53.

The square root of 687923990 is about 26228.3051301452. The cubic root of 687923990 is about 882.7684807759.

The spelling of 687923990 in words is "six hundred eighty-seven million, nine hundred twenty-three thousand, nine hundred ninety".