1231442551 has 2 divisors, whose sum is σ = 1231442552. Its totient is φ = 1231442550.

The previous prime is 1231442519. The next prime is 1231442579. The reversal of 1231442551 is 1552441321.

It is an a-pointer prime, because the next prime (1231442579) can be obtained adding 1231442551 to its sum of digits (28).

It is a strong prime.

It is an emirp because it is prime and its reverse (1552441321) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1231442551 - 2⁵ = 1231442519 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1231442951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 615721275 + 615721276.

It is an arithmetic number, because the mean of its divisors is an integer number (615721276).

Almost surely, 2^1231442551 is an apocalyptic number.

1231442551 is a deficient number, since it is larger than the sum of its proper divisors (1).

1231442551 is an equidigital number, since it uses as much as digits as its factorization.

1231442551 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4800, while the sum is 28.

The square root of 1231442551 is about 35091.9157499274. The cubic root of 1231442551 is about 1071.8599701882.

Adding to 1231442551 its reverse (1552441321), we get a palindrome (2783883872).

The spelling of 1231442551 in words is "one billion, two hundred thirty-one million, four hundred forty-two thousand, five hundred fifty-one".