561420779 has 2 divisors, whose sum is σ = 561420780. Its totient is φ = 561420778.

The previous prime is 561420709. The next prime is 561420787. The reversal of 561420779 is 977024165.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 561420779 - 2²⁰ = 560372203 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (561420709) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280710389 + 280710390.

It is an arithmetic number, because the mean of its divisors is an integer number (280710390).

Almost surely, 2^561420779 is an apocalyptic number.

561420779 is a deficient number, since it is larger than the sum of its proper divisors (1).

561420779 is an equidigital number, since it uses as much as digits as its factorization.

561420779 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 105840, while the sum is 41.

The square root of 561420779 is about 23694.3195513186. The cubic root of 561420779 is about 824.9535469406.

The spelling of 561420779 in words is "five hundred sixty-one million, four hundred twenty thousand, seven hundred seventy-nine".