1265964772801 has 3 divisors (see below), whose sum is σ = 1265965897953. Its totient is φ = 1265963647650.

The previous prime is 1265964772783. The next prime is 1265964772859. The reversal of 1265964772801 is 1082774695621.

The square root of 1265964772801 is 1125151.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1265964772801 - 2¹³ = 1265964764609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265964782801) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 562576 + ... + 1687726.

It is an arithmetic number, because the mean of its divisors is an integer number (421988632651).

Almost surely, 2^{1265964772801} is an apocalyptic number.

1265964772801 is the 1125151-st square number.

1265964772801 is the 562576-th centered octagonal number.

It is an amenable number.

1265964772801 is a deficient number, since it is larger than the sum of its proper divisors (1125152).

1265964772801 is an frugal number, since it uses more digits than its factorization.

1265964772801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2250302 (or 1125151 counting only the distinct ones).

The product of its (nonzero) digits is 10160640, while the sum is 58.

The spelling of 1265964772801 in words is "one trillion, two hundred sixty-five billion, nine hundred sixty-four million, seven hundred seventy-two thousand, eight hundred one".