1265778633 has 12 divisors (see below), whose sum is σ = 1963248720. Its totient is φ = 723301992.

The previous prime is 1265778611. The next prime is 1265778641. The reversal of 1265778633 is 3368775621.

It is not a de Polignac number, because 1265778633 - 2¹⁴ = 1265762249 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1265778643) 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, 4305223 + ... + 4305516.

It is an arithmetic number, because the mean of its divisors is an integer number (163604060).

Almost surely, 2^1265778633 is an apocalyptic number.

It is an amenable number.

1265778633 is a deficient number, since it is larger than the sum of its proper divisors (697470087).

1265778633 is an equidigital number, since it uses as much as digits as its factorization.

1265778633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8610756 (or 8610749 counting only the distinct ones).

The product of its digits is 1270080, while the sum is 48.

The square root of 1265778633 is about 35577.7828567211. The cubic root of 1265778633 is about 1081.7309442813.

The spelling of 1265778633 in words is "one billion, two hundred sixty-five million, seven hundred seventy-eight thousand, six hundred thirty-three".