1265858881 has 8 divisors (see below), whose sum is σ = 1446943104. Its totient is φ = 1084836480.

The previous prime is 1265858861. The next prime is 1265858921. The reversal of 1265858881 is 1888585621.

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

It is not a de Polignac number, because 1265858881 - 2²³ = 1257470273 is a prime.

It is a super-2 number, since 2×1265858881² = 3204797413213144322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265858801) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 43356 + ... + 66418.

It is an arithmetic number, because the mean of its divisors is an integer number (180867888).

Almost surely, 2^1265858881 is an apocalyptic number.

It is an amenable number.

1265858881 is a deficient number, since it is larger than the sum of its proper divisors (181084223).

1265858881 is an equidigital number, since it uses as much as digits as its factorization.

1265858881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30911.

The product of its digits is 1228800, while the sum is 52.

The square root of 1265858881 is about 35578.9106213217. The cubic root of 1265858881 is about 1081.7538037050.

The spelling of 1265858881 in words is "one billion, two hundred sixty-five million, eight hundred fifty-eight thousand, eight hundred eighty-one".