1265220355 has 64 divisors (see below), whose sum is σ = 1875640320. Its totient is φ = 800150400.

The previous prime is 1265220349. The next prime is 1265220403. The reversal of 1265220355 is 5530225621.

It is a happy number.

It is not a de Polignac number, because 1265220355 - 2⁹ = 1265219843 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 5996200 + ... + 5996410.

It is an arithmetic number, because the mean of its divisors is an integer number (29306880).

Almost surely, 2^1265220355 is an apocalyptic number.

1265220355 is a deficient number, since it is larger than the sum of its proper divisors (610419965).

1265220355 is a wasteful number, since it uses less digits than its factorization.

1265220355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 440.

The product of its (nonzero) digits is 18000, while the sum is 31.

The square root of 1265220355 is about 35569.9361118347. The cubic root of 1265220355 is about 1081.5718866126.

Adding to 1265220355 its reverse (5530225621), we get a palindrome (6795445976).

The spelling of 1265220355 in words is "one billion, two hundred sixty-five million, two hundred twenty thousand, three hundred fifty-five".