1561715101 has 2 divisors, whose sum is σ = 1561715102. Its totient is φ = 1561715100.

The previous prime is 1561715087. The next prime is 1561715123. The reversal of 1561715101 is 1015171651.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1482327001 + 79388100 = 38501^2 + 8910^2 .

It is a cyclic number.

It is not a de Polignac number, because 1561715101 - 2⁵ = 1561715069 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1561715101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561715401) 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, 780857550 + 780857551.

It is an arithmetic number, because the mean of its divisors is an integer number (780857551).

Almost surely, 2^1561715101 is an apocalyptic number.

It is an amenable number.

1561715101 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561715101 is an equidigital number, since it uses as much as digits as its factorization.

1561715101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1050, while the sum is 28.

The square root of 1561715101 is about 39518.5412306679. The cubic root of 1561715101 is about 1160.2028730092.

Adding to 1561715101 its reverse (1015171651), we get a palindrome (2576886752).

The spelling of 1561715101 in words is "one billion, five hundred sixty-one million, seven hundred fifteen thousand, one hundred one".