261068640 has 96 divisors (see below), whose sum is σ = 939859200. Its totient is φ = 59672064.

The previous prime is 261068629. The next prime is 261068651. The reversal of 261068640 is 46860162.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (261068629) and next prime (261068651).

It is a tau number, because it is divible by the number of its divisors (96).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 35490 + ... + 42209.

It is an arithmetic number, because the mean of its divisors is an integer number (9790200).

Almost surely, 2^261068640 is an apocalyptic number.

261068640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261068640 is an abundant number, since it is smaller than the sum of its proper divisors (678790560).

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

261068640 is a wasteful number, since it uses less digits than its factorization.

261068640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77724 (or 77716 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 33.

The square root of 261068640 is about 16157.6186364204. The cubic root of 261068640 is about 639.1236704119.

The spelling of 261068640 in words is "two hundred sixty-one million, sixty-eight thousand, six hundred forty".