1264121263 has 4 divisors (see below), whose sum is σ = 1265604088. Its totient is φ = 1262638440.

The previous prime is 1264121237. The next prime is 1264121279. The reversal of 1264121263 is 3621214621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3621214621 = 59 ⋅61376519.

It is a cyclic number.

It is not a de Polignac number, because 1264121263 - 2⁵ = 1264121231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1264121203) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 740133 + ... + 741838.

It is an arithmetic number, because the mean of its divisors is an integer number (316401022).

Almost surely, 2^1264121263 is an apocalyptic number.

1264121263 is a deficient number, since it is larger than the sum of its proper divisors (1482825).

1264121263 is an equidigital number, since it uses as much as digits as its factorization.

1264121263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1482824.

The product of its digits is 3456, while the sum is 28.

The square root of 1264121263 is about 35554.4830225388. The cubic root of 1264121263 is about 1081.2586101178.

Adding to 1264121263 its reverse (3621214621), we get a palindrome (4885335884).

The spelling of 1264121263 in words is "one billion, two hundred sixty-four million, one hundred twenty-one thousand, two hundred sixty-three".