1209945263 has 4 divisors (see below), whose sum is σ = 1210191168. Its totient is φ = 1209699360.

The previous prime is 1209945259. The next prime is 1209945281. The reversal of 1209945263 is 3625499021.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1209945263 - 2² = 1209945259 is a prime.

It is a super-2 number, since 2×1209945263² = 2927935078912278338, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1209945263.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1203945263) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 115418 + ... + 125463.

It is an arithmetic number, because the mean of its divisors is an integer number (302547792).

Almost surely, 2^1209945263 is an apocalyptic number.

1209945263 is a deficient number, since it is larger than the sum of its proper divisors (245905).

1209945263 is an equidigital number, since it uses as much as digits as its factorization.

1209945263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 245904.

The product of its (nonzero) digits is 116640, while the sum is 41.

The square root of 1209945263 is about 34784.2674638981. The cubic root of 1209945263 is about 1065.5861682407.

The spelling of 1209945263 in words is "one billion, two hundred nine million, nine hundred forty-five thousand, two hundred sixty-three".