1265451505 has 4 divisors (see below), whose sum is σ = 1518541812. Its totient is φ = 1012361200.

The previous prime is 1265451503. The next prime is 1265451521. The reversal of 1265451505 is 5051545621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5051545621 = 11299 ⋅447079.

It can be written as a sum of positive squares in 2 ways, for example, as 762256881 + 503194624 = 27609^2 + 22432^2 .

It is not a de Polignac number, because 1265451505 - 2¹ = 1265451503 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265451503) 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, 126545146 + ... + 126545155.

It is an arithmetic number, because the mean of its divisors is an integer number (379635453).

Almost surely, 2^1265451505 is an apocalyptic number.

It is an amenable number.

1265451505 is a deficient number, since it is larger than the sum of its proper divisors (253090307).

1265451505 is an equidigital number, since it uses as much as digits as its factorization.

1265451505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 253090306.

The product of its (nonzero) digits is 30000, while the sum is 34.

The square root of 1265451505 is about 35573.1851961558. The cubic root of 1265451505 is about 1081.6377486888.

The spelling of 1265451505 in words is "one billion, two hundred sixty-five million, four hundred fifty-one thousand, five hundred five".