1255212421 has 2 divisors, whose sum is σ = 1255212422. Its totient is φ = 1255212420.

The previous prime is 1255212401. The next prime is 1255212437. The reversal of 1255212421 is 1242125521.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1224020196 + 31192225 = 34986^2 + 5585^2 .

It is a cyclic number.

It is not a de Polignac number, because 1255212421 - 2¹¹ = 1255210373 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1255212401) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 627606210 + 627606211.

It is an arithmetic number, because the mean of its divisors is an integer number (627606211).

Almost surely, 2^1255212421 is an apocalyptic number.

It is an amenable number.

1255212421 is a deficient number, since it is larger than the sum of its proper divisors (1).

1255212421 is an equidigital number, since it uses as much as digits as its factorization.

1255212421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1600, while the sum is 25.

The square root of 1255212421 is about 35428.9771373660. The cubic root of 1255212421 is about 1078.7125780117.

Adding to 1255212421 its reverse (1242125521), we get a palindrome (2497337942).

The spelling of 1255212421 in words is "one billion, two hundred fifty-five million, two hundred twelve thousand, four hundred twenty-one".