840680693 has 2 divisors, whose sum is σ = 840680694. Its totient is φ = 840680692.

The previous prime is 840680641. The next prime is 840680699. The reversal of 840680693 is 396086048.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 770506564 + 70174129 = 27758^2 + 8377^2 .

It is a cyclic number.

It is not a de Polignac number, because 840680693 - 2¹² = 840676597 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (840680699) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 420340346 + 420340347.

It is an arithmetic number, because the mean of its divisors is an integer number (420340347).

Almost surely, 2^840680693 is an apocalyptic number.

It is an amenable number.

840680693 is a deficient number, since it is larger than the sum of its proper divisors (1).

840680693 is an equidigital number, since it uses as much as digits as its factorization.

840680693 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 44.

The square root of 840680693 is about 28994.4941842413. The cubic root of 840680693 is about 943.7935924311.

The spelling of 840680693 in words is "eight hundred forty million, six hundred eighty thousand, six hundred ninety-three".