688920899 has 4 divisors (see below), whose sum is σ = 695742000. Its totient is φ = 682099800.

The previous prime is 688920887. The next prime is 688920901. The reversal of 688920899 is 998029886.

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

It is a cyclic number.

It is not a de Polignac number, because 688920899 - 2²⁰ = 687872323 is a prime.

It is a super-2 number, since 2×688920899² = 949224010157936402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (688920299) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3410399 + ... + 3410600.

It is an arithmetic number, because the mean of its divisors is an integer number (173935500).

Almost surely, 2^688920899 is an apocalyptic number.

688920899 is a deficient number, since it is larger than the sum of its proper divisors (6821101).

688920899 is a wasteful number, since it uses less digits than its factorization.

688920899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6821100.

The product of its (nonzero) digits is 4478976, while the sum is 59.

The square root of 688920899 is about 26247.3026995156. The cubic root of 688920899 is about 883.1946979613.

The spelling of 688920899 in words is "six hundred eighty-eight million, nine hundred twenty thousand, eight hundred ninety-nine".