1266422251 has 4 divisors (see below), whose sum is σ = 1321484112. Its totient is φ = 1211360392.

The previous prime is 1266422237. The next prime is 1266422279. The reversal of 1266422251 is 1522246621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1522246621 = 7 ⋅217463803.

It is a cyclic number.

It is not a de Polignac number, because 1266422251 - 2¹¹ = 1266420203 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1266422221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27530896 + ... + 27530941.

It is an arithmetic number, because the mean of its divisors is an integer number (330371028).

Almost surely, 2^1266422251 is an apocalyptic number.

1266422251 is a deficient number, since it is larger than the sum of its proper divisors (55061861).

1266422251 is an equidigital number, since it uses as much as digits as its factorization.

1266422251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55061860.

The product of its digits is 11520, while the sum is 31.

The square root of 1266422251 is about 35586.8269307619. The cubic root of 1266422251 is about 1081.9142579398.

Adding to 1266422251 its reverse (1522246621), we get a palindrome (2788668872).

The spelling of 1266422251 in words is "one billion, two hundred sixty-six million, four hundred twenty-two thousand, two hundred fifty-one".