1263000261 has 16 divisors (see below), whose sum is σ = 1784813184. Its totient is φ = 791691264.

The previous prime is 1263000259. The next prime is 1263000269. The reversal of 1263000261 is 1620003621.

It is a happy number.

It is not a de Polignac number, because 1263000261 - 2¹ = 1263000259 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1263000269) 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 15 ways as a sum of consecutive naturals, for example, 42565 + ... + 65861.

It is an arithmetic number, because the mean of its divisors is an integer number (111550824).

Almost surely, 2^1263000261 is an apocalyptic number.

It is an amenable number.

1263000261 is a deficient number, since it is larger than the sum of its proper divisors (521812923).

1263000261 is a wasteful number, since it uses less digits than its factorization.

1263000261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24380.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 1263000261 is about 35538.7149598856. The cubic root of 1263000261 is about 1080.9389014620.

Adding to 1263000261 its reverse (1620003621), we get a palindrome (2883003882).

The spelling of 1263000261 in words is "one billion, two hundred sixty-three million, two hundred sixty-one", and thus it is an aban number.