265136640 has 320 divisors, whose sum is σ = 942796800. Its totient is φ = 63258624.

The previous prime is 265136639. The next prime is 265136671. The reversal of 265136640 is 46631562.

It is a tau number, because it is divible by the number of its divisors (320).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3356121 + ... + 3356199.

It is an arithmetic number, because the mean of its divisors is an integer number (2946240).

Almost surely, 2^265136640 is an apocalyptic number.

265136640 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 265136640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (471398400).

265136640 is an abundant number, since it is smaller than the sum of its proper divisors (677660160).

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

265136640 is a wasteful number, since it uses less digits than its factorization.

265136640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 147 (or 131 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 33.

The square root of 265136640 is about 16283.0169194778. The cubic root of 265136640 is about 642.4262074153.

It can be divided in two parts, 26513 and 6640, that added together give a triangular number (33153 = T₂₅₇).

The spelling of 265136640 in words is "two hundred sixty-five million, one hundred thirty-six thousand, six hundred forty".