689527638749 has 2 divisors, whose sum is σ = 689527638750. Its totient is φ = 689527638748.

The previous prime is 689527638733. The next prime is 689527638757. The reversal of 689527638749 is 947836725986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 442823702500 + 246703936249 = 665450^2 + 496693^2 .

It is a cyclic number.

It is not a de Polignac number, because 689527638749 - 2⁴ = 689527638733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (689527635749) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344763819374 + 344763819375.

It is an arithmetic number, because the mean of its divisors is an integer number (344763819375).

Almost surely, 2^689527638749 is an apocalyptic number.

It is an amenable number.

689527638749 is a deficient number, since it is larger than the sum of its proper divisors (1).

689527638749 is an equidigital number, since it uses as much as digits as its factorization.

689527638749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1097349120, while the sum is 74.

The spelling of 689527638749 in words is "six hundred eighty-nine billion, five hundred twenty-seven million, six hundred thirty-eight thousand, seven hundred forty-nine".