1561117 has 2 divisors, whose sum is σ = 1561118. Its totient is φ = 1561116.

The previous prime is 1561111. The next prime is 1561121. The reversal of 1561117 is 7111651.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1012036 + 549081 = 1006^2 + 741^2 .

It is an emirp because it is prime and its reverse (7111651) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1561117 - 2¹⁹ = 1036829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1561111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 780558 + 780559.

It is an arithmetic number, because the mean of its divisors is an integer number (780559).

2^1561117 is an apocalyptic number.

It is an amenable number.

1561117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1561117 is an equidigital number, since it uses as much as digits as its factorization.

1561117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 210, while the sum is 22.

The square root of 1561117 is about 1249.4466775337. The cubic root of 1561117 is about 116.0054743750.

Adding to 1561117 its reverse (7111651), we get a palindrome (8672768).

The spelling of 1561117 in words is "one million, five hundred sixty-one thousand, one hundred seventeen".