260909640 has 128 divisors (see below), whose sum is σ = 897868800. Its totient is φ = 67322880.

The previous prime is 260909639. The next prime is 260909657. The reversal of 260909640 is 46909062.

260909640 is a `hidden beast` number, since 2 + 6 + 0 + 9 + 0 + 9 + 640 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 260909595 and 260909604.

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, 29584 + ... + 37376.

It is an arithmetic number, because the mean of its divisors is an integer number (7014600).

Almost surely, 2^260909640 is an apocalyptic number.

260909640 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 260909640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (448934400).

260909640 is an abundant number, since it is smaller than the sum of its proper divisors (636959160).

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

260909640 is a wasteful number, since it uses less digits than its factorization.

260909640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7844 (or 7834 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 36.

The square root of 260909640 is about 16152.6976075205. The cubic root of 260909640 is about 638.9938944511.

The spelling of 260909640 in words is "two hundred sixty million, nine hundred nine thousand, six hundred forty".