688975581 has 16 divisors (see below), whose sum is σ = 1050407424. Its totient is φ = 393497904.

The previous prime is 688975579. The next prime is 688975597. The reversal of 688975581 is 185579886.

It is a happy number.

It is not a de Polignac number, because 688975581 - 2¹ = 688975579 is a prime.

It is a super-2 number, since 2×688975581² = 949374702428575122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (688975501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39790 + ... + 54416.

It is an arithmetic number, because the mean of its divisors is an integer number (65650464).

Almost surely, 2^688975581 is an apocalyptic number.

It is an amenable number.

688975581 is a deficient number, since it is larger than the sum of its proper divisors (361431843).

688975581 is a wasteful number, since it uses less digits than its factorization.

688975581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16880.

The product of its digits is 4838400, while the sum is 57.

The square root of 688975581 is about 26248.3443477870. The cubic root of 688975581 is about 883.2180647343.

The spelling of 688975581 in words is "six hundred eighty-eight million, nine hundred seventy-five thousand, five hundred eighty-one".