261334540 has 24 divisors (see below), whose sum is σ = 581085792. Its totient is φ = 98384640.

The previous prime is 261334537. The next prime is 261334543. The reversal of 261334540 is 45433162.

261334540 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261334537) and next prime (261334543).

It is a junction number, because it is equal to n+sod(n) for n = 261334499 and 261334508.

It is not an unprimeable number, because it can be changed into a prime (261334543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 383976 + ... + 384655.

It is an arithmetic number, because the mean of its divisors is an integer number (24211908).

Almost surely, 2^261334540 is an apocalyptic number.

261334540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

261334540 is an abundant number, since it is smaller than the sum of its proper divisors (319751252).

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

261334540 is a wasteful number, since it uses less digits than its factorization.

261334540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 768657 (or 768655 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 28.

The square root of 261334540 is about 16165.8448588374. The cubic root of 261334540 is about 639.3405805709.

The spelling of 261334540 in words is "two hundred sixty-one million, three hundred thirty-four thousand, five hundred forty".