631090561 has 2 divisors, whose sum is σ = 631090562. Its totient is φ = 631090560.

The previous prime is 631090531. The next prime is 631090627. The reversal of 631090561 is 165090136.

631090561 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 442302961 + 188787600 = 21031^2 + 13740^2 .

It is a cyclic number.

It is not a de Polignac number, because 631090561 - 2⁷ = 631090433 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (631090531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 315545280 + 315545281.

It is an arithmetic number, because the mean of its divisors is an integer number (315545281).

Almost surely, 2^631090561 is an apocalyptic number.

It is an amenable number.

631090561 is a deficient number, since it is larger than the sum of its proper divisors (1).

631090561 is an equidigital number, since it uses as much as digits as its factorization.

631090561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4860, while the sum is 31.

The square root of 631090561 is about 25121.5158977320. The cubic root of 631090561 is about 857.7562572524.

The spelling of 631090561 in words is "six hundred thirty-one million, ninety thousand, five hundred sixty-one".