1321155265 has 8 divisors (see below), whose sum is σ = 1585695168. Its totient is φ = 1056718320.

The previous prime is 1321155217. The next prime is 1321155271. The reversal of 1321155265 is 5625511231.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1321155265 - 2¹³ = 1321147073 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6070 + ... + 51760.

It is an arithmetic number, because the mean of its divisors is an integer number (198211896).

Almost surely, 2^1321155265 is an apocalyptic number.

It is an amenable number.

1321155265 is a deficient number, since it is larger than the sum of its proper divisors (264539903).

1321155265 is an equidigital number, since it uses as much as digits as its factorization.

1321155265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51479.

The product of its digits is 9000, while the sum is 31.

The square root of 1321155265 is about 36347.6995833299. The cubic root of 1321155265 is about 1097.2812376278.

Adding to 1321155265 its reverse (5625511231), we get a palindrome (6946666496).

The spelling of 1321155265 in words is "one billion, three hundred twenty-one million, one hundred fifty-five thousand, two hundred sixty-five".