690843677 has 2 divisors, whose sum is σ = 690843678. Its totient is φ = 690843676.

The previous prime is 690843661. The next prime is 690843679. The reversal of 690843677 is 776348096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 687435961 + 3407716 = 26219^2 + 1846^2 .

It is a cyclic number.

It is not a de Polignac number, because 690843677 - 2⁴ = 690843661 is a prime.

Together with 690843679, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (690843679) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345421838 + 345421839.

It is an arithmetic number, because the mean of its divisors is an integer number (345421839).

Almost surely, 2^690843677 is an apocalyptic number.

It is an amenable number.

690843677 is a deficient number, since it is larger than the sum of its proper divisors (1).

690843677 is an equidigital number, since it uses as much as digits as its factorization.

690843677 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1524096, while the sum is 50.

The square root of 690843677 is about 26283.9052844131. The cubic root of 690843677 is about 884.0156000912.

The spelling of 690843677 in words is "six hundred ninety million, eight hundred forty-three thousand, six hundred seventy-seven".