1231657117 has 2 divisors, whose sum is σ = 1231657118. Its totient is φ = 1231657116.

The previous prime is 1231657109. The next prime is 1231657171. The reversal of 1231657117 is 7117561321.

It is a happy number.

Together with next prime (1231657171) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 757680676 + 473976441 = 27526^2 + 21771^2 .

It is a cyclic number.

It is not a de Polignac number, because 1231657117 - 2³ = 1231657109 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231637117) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615828558 + 615828559.

It is an arithmetic number, because the mean of its divisors is an integer number (615828559).

Almost surely, 2^1231657117 is an apocalyptic number.

It is an amenable number.

1231657117 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231657117 is an equidigital number, since it uses as much as digits as its factorization.

1231657117 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8820, while the sum is 34.

The square root of 1231657117 is about 35094.9728166300. The cubic root of 1231657117 is about 1071.9222200404.

The spelling of 1231657117 in words is "one billion, two hundred thirty-one million, six hundred fifty-seven thousand, one hundred seventeen".