1661117 has 2 divisors, whose sum is σ = 1661118. Its totient is φ = 1661116.

The previous prime is 1661111. The next prime is 1661123. The reversal of 1661117 is 7111661.

It is a balanced prime because it is at equal distance from previous prime (1661111) and next prime (1661123).

It can be written as a sum of positive squares in only one way, i.e., 1104601 + 556516 = 1051^2 + 746^2 .

It is a cyclic number.

It is not a de Polignac number, because 1661117 - 2¹² = 1657021 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1661092 and 1661101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1661111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 830558 + 830559.

It is an arithmetic number, because the mean of its divisors is an integer number (830559).

2^1661117 is an apocalyptic number.

It is an amenable number.

1661117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1661117 is an equidigital number, since it uses as much as digits as its factorization.

1661117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 252, while the sum is 23.

The square root of 1661117 is about 1288.8432798444. The cubic root of 1661117 is about 118.4313666667.

Adding to 1661117 its reverse (7111661), we get a palindrome (8772778).

The spelling of 1661117 in words is "one million, six hundred sixty-one thousand, one hundred seventeen".