1263126321 has 12 divisors (see below), whose sum is σ = 1826407440. Its totient is φ = 841211160.

The previous prime is 1263126311. The next prime is 1263126323. The reversal of 1263126321 is 1236213621.

1263126321 is a `hidden beast` number, since 1 + 2 + 631 + 2 + 6 + 3 + 21 = 666.

It is not a de Polignac number, because 1263126321 - 2¹⁸ = 1262864177 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (1263126323) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 63531 + ... + 81008.

It is an arithmetic number, because the mean of its divisors is an integer number (152200620).

Almost surely, 2^1263126321 is an apocalyptic number.

It is an amenable number.

1263126321 is a deficient number, since it is larger than the sum of its proper divisors (563281119).

1263126321 is a wasteful number, since it uses less digits than its factorization.

1263126321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145516 (or 145513 counting only the distinct ones).

The product of its digits is 2592, while the sum is 27.

The square root of 1263126321 is about 35540.4884744146. The cubic root of 1263126321 is about 1080.9748630868.

Adding to 1263126321 its reverse (1236213621), we get a palindrome (2499339942).

The spelling of 1263126321 in words is "one billion, two hundred sixty-three million, one hundred twenty-six thousand, three hundred twenty-one".