265491720 has 384 divisors, whose sum is σ = 1018967040. Its totient is φ = 59351040.

The previous prime is 265491697. The next prime is 265491727. The reversal of 265491720 is 27194562.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (265491727) by changing a digit.

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 95 ways as a sum of consecutive naturals, for example, 3739285 + ... + 3739355.

It is an arithmetic number, because the mean of its divisors is an integer number (2653560).

Almost surely, 2^265491720 is an apocalyptic number.

265491720 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 265491720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (509483520).

265491720 is an abundant number, since it is smaller than the sum of its proper divisors (753475320).

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

265491720 is a wasteful number, since it uses less digits than its factorization.

265491720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165 (or 158 counting only the distinct ones).

The product of its (nonzero) digits is 30240, while the sum is 36.

The square root of 265491720 is about 16293.9166562248. The cubic root of 265491720 is about 642.7128658233.

The spelling of 265491720 in words is "two hundred sixty-five million, four hundred ninety-one thousand, seven hundred twenty".