561139903 has 2 divisors, whose sum is σ = 561139904. Its totient is φ = 561139902.

The previous prime is 561139883. The next prime is 561139933. The reversal of 561139903 is 309931165.

561139903 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 is a cyclic number.

It is not a de Polignac number, because 561139903 - 2⁹ = 561139391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561139933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280569951 + 280569952.

It is an arithmetic number, because the mean of its divisors is an integer number (280569952).

Almost surely, 2^561139903 is an apocalyptic number.

561139903 is a deficient number, since it is larger than the sum of its proper divisors (1).

561139903 is an equidigital number, since it uses as much as digits as its factorization.

561139903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21870, while the sum is 37.

The square root of 561139903 is about 23688.3917351938. The cubic root of 561139903 is about 824.8159506178.

The spelling of 561139903 in words is "five hundred sixty-one million, one hundred thirty-nine thousand, nine hundred three".