1265601161 has 8 divisors (see below), whose sum is σ = 1414330848. Its totient is φ = 1122484000.

The previous prime is 1265601149. The next prime is 1265601163. The reversal of 1265601161 is 1611065621.

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

It is not a de Polignac number, because 1265601161 - 2¹⁸ = 1265339017 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1265601163) 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, 1402655 + ... + 1403556.

It is an arithmetic number, because the mean of its divisors is an integer number (176791356).

Almost surely, 2^1265601161 is an apocalyptic number.

1265601161 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1265601161 is a deficient number, since it is larger than the sum of its proper divisors (148729687).

1265601161 is a wasteful number, since it uses less digits than its factorization.

1265601161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2806263.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 1265601161 is about 35575.2886284848. The cubic root of 1265601161 is about 1081.6803862237.

Adding to 1265601161 its reverse (1611065621), we get a palindrome (2876666782).

It can be divided in two parts, 126560 and 1161, that added together give a palindrome (127721).

The spelling of 1265601161 in words is "one billion, two hundred sixty-five million, six hundred one thousand, one hundred sixty-one".