688923706 has 4 divisors (see below), whose sum is σ = 1033385562. Its totient is φ = 344461852.

The previous prime is 688923689. The next prime is 688923713. The reversal of 688923706 is 607329886.

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

It can be written as a sum of positive squares in only one way, i.e., 391050625 + 297873081 = 19775^2 + 17259^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 688923706.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 172230925 + ... + 172230928.

Almost surely, 2^688923706 is an apocalyptic number.

688923706 is a deficient number, since it is larger than the sum of its proper divisors (344461856).

688923706 is a wasteful number, since it uses less digits than its factorization.

688923706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344461855.

The product of its (nonzero) digits is 870912, while the sum is 49.

The square root of 688923706 is about 26247.3561716223. The cubic root of 688923706 is about 883.1958974817.

The spelling of 688923706 in words is "six hundred eighty-eight million, nine hundred twenty-three thousand, seven hundred six".