265266640 has 40 divisors (see below), whose sum is σ = 653027400. Its totient is φ = 99864576.

The previous prime is 265266587. The next prime is 265266647. The reversal of 265266640 is 46662562.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 14107536 + 251159104 = 3756^2 + 15848^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 265266640.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (265266647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96165 + ... + 98884.

It is an arithmetic number, because the mean of its divisors is an integer number (16325685).

Almost surely, 2^265266640 is an apocalyptic number.

265266640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

265266640 is an abundant number, since it is smaller than the sum of its proper divisors (387760760).

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

265266640 is a wasteful number, since it uses less digits than its factorization.

265266640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 195079 (or 195073 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 37.

The square root of 265266640 is about 16287.0083195165. The cubic root of 265266640 is about 642.5311869473.

The spelling of 265266640 in words is "two hundred sixty-five million, two hundred sixty-six thousand, six hundred forty".