690255649 has 2 divisors, whose sum is σ = 690255650. Its totient is φ = 690255648.

The previous prime is 690255613. The next prime is 690255659. The reversal of 690255649 is 946552096.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 495374049 + 194881600 = 22257^2 + 13960^2 .

It is a cyclic number.

It is not a de Polignac number, because 690255649 - 2¹⁷ = 690124577 is a prime.

It is a super-2 number, since 2×690255649² = 952905721952822402, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 690255599 and 690255608.

It is not a weakly prime, because it can be changed into another prime (690255659) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345127824 + 345127825.

It is an arithmetic number, because the mean of its divisors is an integer number (345127825).

Almost surely, 2^690255649 is an apocalyptic number.

It is an amenable number.

690255649 is a deficient number, since it is larger than the sum of its proper divisors (1).

690255649 is an equidigital number, since it uses as much as digits as its factorization.

690255649 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 583200, while the sum is 46.

The square root of 690255649 is about 26272.7168180225. The cubic root of 690255649 is about 883.7647119382.

The spelling of 690255649 in words is "six hundred ninety million, two hundred fifty-five thousand, six hundred forty-nine".