1263889264 has 20 divisors (see below), whose sum is σ = 2671402680. Its totient is φ = 574495040.

The previous prime is 1263889219. The next prime is 1263889283. The reversal of 1263889264 is 4629883621.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3590419 + ... + 3590770.

It is an arithmetic number, because the mean of its divisors is an integer number (133570134).

Almost surely, 2^1263889264 is an apocalyptic number.

It is an amenable number.

1263889264 is an abundant number, since it is smaller than the sum of its proper divisors (1407513416).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1263889264 is a wasteful number, since it uses less digits than its factorization.

1263889264 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7181208 (or 7181202 counting only the distinct ones).

The product of its digits is 995328, while the sum is 49.

The square root of 1263889264 is about 35551.2202884796. The cubic root of 1263889264 is about 1081.1924597488.

The spelling of 1263889264 in words is "one billion, two hundred sixty-three million, eight hundred eighty-nine thousand, two hundred sixty-four".