1663615117 has 2 divisors, whose sum is σ = 1663615118. Its totient is φ = 1663615116.

The previous prime is 1663615103. The next prime is 1663615123. The reversal of 1663615117 is 7115163661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1656571401 + 7043716 = 40701^2 + 2654^2 .

It is an emirp because it is prime and its reverse (7115163661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1663615117 - 2⁷ = 1663614989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1663615517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 831807558 + 831807559.

It is an arithmetic number, because the mean of its divisors is an integer number (831807559).

Almost surely, 2^1663615117 is an apocalyptic number.

It is an amenable number.

1663615117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1663615117 is an equidigital number, since it uses as much as digits as its factorization.

1663615117 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 37.

The square root of 1663615117 is about 40787.4382255125. The cubic root of 1663615117 is about 1184.9070569867.

Adding to 1663615117 its reverse (7115163661), we get a palindrome (8778778778).

The spelling of 1663615117 in words is "one billion, six hundred sixty-three million, six hundred fifteen thousand, one hundred seventeen".