1232656991 has 2 divisors, whose sum is σ = 1232656992. Its totient is φ = 1232656990.

The previous prime is 1232656981. The next prime is 1232656993. The reversal of 1232656991 is 1996562321.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1232656991 is a prime.

It is a super-2 number, since 2×1232656991² = 3038886514922348162, which contains 22 as substring.

Together with 1232656993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1232656993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 616328495 + 616328496.

It is an arithmetic number, because the mean of its divisors is an integer number (616328496).

Almost surely, 2^1232656991 is an apocalyptic number.

1232656991 is a deficient number, since it is larger than the sum of its proper divisors (1).

1232656991 is an equidigital number, since it uses as much as digits as its factorization.

1232656991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 174960, while the sum is 44.

The square root of 1232656991 is about 35109.2151863296. The cubic root of 1232656991 is about 1072.2122080151.

The spelling of 1232656991 in words is "one billion, two hundred thirty-two million, six hundred fifty-six thousand, nine hundred ninety-one".