1561677427 has 2 divisors, whose sum is σ = 1561677428. Its totient is φ = 1561677426.

The previous prime is 1561677407. The next prime is 1561677457. The reversal of 1561677427 is 7247761651.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1561677427 - 2¹⁵ = 1561644659 is a prime.

It is not a weakly prime, because it can be changed into another prime (1561677407) 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, 780838713 + 780838714.

It is an arithmetic number, because the mean of its divisors is an integer number (780838714).

Almost surely, 2^1561677427 is an apocalyptic number.

1561677427 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561677427 is an equidigital number, since it uses as much as digits as its factorization.

1561677427 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 493920, while the sum is 46.

The square root of 1561677427 is about 39518.0645654617. The cubic root of 1561677427 is about 1160.1935435580.

The spelling of 1561677427 in words is "one billion, five hundred sixty-one million, six hundred seventy-seven thousand, four hundred twenty-seven".