265721040 has 160 divisors (see below), whose sum is σ = 985770240. Its totient is φ = 65401344.

The previous prime is 265721017. The next prime is 265721051. The reversal of 265721040 is 40127562.

265721040 is a `hidden beast` number, since 2 + 657 + 2 + 1 + 0 + 4 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 265720995 and 265721013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 23349 + ... + 32811.

It is an arithmetic number, because the mean of its divisors is an integer number (6161064).

Almost surely, 2^265721040 is an apocalyptic number.

265721040 is a gapful number since it is divisible by the number (20) 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 265721040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (492885120).

265721040 is an abundant number, since it is smaller than the sum of its proper divisors (720049200).

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

265721040 is a wasteful number, since it uses less digits than its factorization.

265721040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9498 (or 9486 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 27.

The square root of 265721040 is about 16300.9521194316. The cubic root of 265721040 is about 642.8978615478.

The spelling of 265721040 in words is "two hundred sixty-five million, seven hundred twenty-one thousand, forty".