1265564160 has 720 divisors, whose sum is σ = 5457909600. Its totient is φ = 269402112.

The previous prime is 1265564129. The next prime is 1265564161. The reversal of 1265564160 is 614655621.

1265564160 is a `hidden beast` number, since 1 + 2 + 6 + 5 + 5 + 641 + 6 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (720).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1265564161) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 21450211 + ... + 21450269.

It is an arithmetic number, because the mean of its divisors is an integer number (7580430).

Almost surely, 2^1265564160 is an apocalyptic number.

1265564160 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1265564160, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2728954800).

1265564160 is an abundant number, since it is smaller than the sum of its proper divisors (4192345440).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1265564160 is a wasteful number, since it uses less digits than its factorization.

1265564160 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121 (or 95 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The square root of 1265564160 is about 35574.7685867386. The cubic root of 1265564160 is about 1081.6698448180.

The spelling of 1265564160 in words is "one billion, two hundred sixty-five million, five hundred sixty-four thousand, one hundred sixty".