1561426049 has 2 divisors, whose sum is σ = 1561426050. Its totient is φ = 1561426048.

The previous prime is 1561426039. The next prime is 1561426067. The reversal of 1561426049 is 9406241651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1394499649 + 166926400 = 37343^2 + 12920^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561426049 - 2⁸ = 1561425793 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (1561426039) 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, 780713024 + 780713025.

It is an arithmetic number, because the mean of its divisors is an integer number (780713025).

Almost surely, 2^1561426049 is an apocalyptic number.

It is an amenable number.

1561426049 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561426049 is an equidigital number, since it uses as much as digits as its factorization.

1561426049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 51840, while the sum is 38.

The square root of 1561426049 is about 39514.8838920223. The cubic root of 1561426049 is about 1160.1312893909.

The spelling of 1561426049 in words is "one billion, five hundred sixty-one million, four hundred twenty-six thousand, forty-nine".