688505494 has 4 divisors (see below), whose sum is σ = 1032758244. Its totient is φ = 344252746.

The previous prime is 688505479. The next prime is 688505533. The reversal of 688505494 is 494505886.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172126372 + ... + 172126375.

It is an arithmetic number, because the mean of its divisors is an integer number (258189561).

Almost surely, 2^688505494 is an apocalyptic number.

688505494 is a deficient number, since it is larger than the sum of its proper divisors (344252750).

688505494 is a wasteful number, since it uses less digits than its factorization.

688505494 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344252749.

The product of its (nonzero) digits is 1382400, while the sum is 49.

The square root of 688505494 is about 26239.3882169535. The cubic root of 688505494 is about 883.0171462473.

The spelling of 688505494 in words is "six hundred eighty-eight million, five hundred five thousand, four hundred ninety-four".