688825961 has 2 divisors, whose sum is σ = 688825962. Its totient is φ = 688825960.

The previous prime is 688825931. The next prime is 688825979. The reversal of 688825961 is 169528886.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 541446361 + 147379600 = 23269^2 + 12140^2 .

It is a cyclic number.

It is not a de Polignac number, because 688825961 - 2⁶ = 688825897 is a prime.

It is not a weakly prime, because it can be changed into another prime (688825931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344412980 + 344412981.

It is an arithmetic number, because the mean of its divisors is an integer number (344412981).

Almost surely, 2^688825961 is an apocalyptic number.

It is an amenable number.

688825961 is a deficient number, since it is larger than the sum of its proper divisors (1).

688825961 is an equidigital number, since it uses as much as digits as its factorization.

688825961 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1658880, while the sum is 53.

The square root of 688825961 is about 26245.4941085132. The cubic root of 688825961 is about 883.1541260126.

The spelling of 688825961 in words is "six hundred eighty-eight million, eight hundred twenty-five thousand, nine hundred sixty-one".