681525769 has 2 divisors, whose sum is σ = 681525770. Its totient is φ = 681525768.

The previous prime is 681525743. The next prime is 681525799. The reversal of 681525769 is 967525186.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 620607744 + 60918025 = 24912^2 + 7805^2 .

It is a cyclic number.

It is not a de Polignac number, because 681525769 - 2¹⁹ = 681001481 is a prime.

It is a super-2 number, since 2×681525769² = 928954747622082722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (681525799) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 340762884 + 340762885.

It is an arithmetic number, because the mean of its divisors is an integer number (340762885).

Almost surely, 2^681525769 is an apocalyptic number.

It is an amenable number.

681525769 is a deficient number, since it is larger than the sum of its proper divisors (1).

681525769 is an equidigital number, since it uses as much as digits as its factorization.

681525769 is an evil number, because the sum of its binary digits is even.

The product of its digits is 907200, while the sum is 49.

The square root of 681525769 is about 26106.0485137066. The cubic root of 681525769 is about 880.0231437612.

The spelling of 681525769 in words is "six hundred eighty-one million, five hundred twenty-five thousand, seven hundred sixty-nine".