1231661323 has 2 divisors, whose sum is σ = 1231661324. Its totient is φ = 1231661322.

The previous prime is 1231661311. The next prime is 1231661351. The reversal of 1231661323 is 3231661321.

It is an a-pointer prime, because the next prime (1231661351) can be obtained adding 1231661323 to its sum of digits (28).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1231661323 - 2⁹ = 1231660811 is a prime.

It is a super-2 number, since 2×1231661323² = 3033979229148220658, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1231661291 and 1231661300.

It is not a weakly prime, because it can be changed into another prime (1231661303) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615830661 + 615830662.

It is an arithmetic number, because the mean of its divisors is an integer number (615830662).

Almost surely, 2^1231661323 is an apocalyptic number.

1231661323 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231661323 is an equidigital number, since it uses as much as digits as its factorization.

1231661323 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3888, while the sum is 28.

The square root of 1231661323 is about 35095.0327396912. The cubic root of 1231661323 is about 1071.9234402121.

The spelling of 1231661323 in words is "one billion, two hundred thirty-one million, six hundred sixty-one thousand, three hundred twenty-three".