261237345 has 16 divisors (see below), whose sum is σ = 419228160. Its totient is φ = 138910464.

The previous prime is 261237343. The next prime is 261237359. The reversal of 261237345 is 543732162.

It is not a de Polignac number, because 261237345 - 2¹ = 261237343 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (261237343) 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 15 ways as a sum of consecutive naturals, for example, 20785 + ... + 30894.

It is an arithmetic number, because the mean of its divisors is an integer number (26201760).

Almost surely, 2^261237345 is an apocalyptic number.

It is an amenable number.

261237345 is a deficient number, since it is larger than the sum of its proper divisors (157990815).

261237345 is a wasteful number, since it uses less digits than its factorization.

261237345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52024.

The product of its digits is 30240, while the sum is 33.

The square root of 261237345 is about 16162.8383955294. The cubic root of 261237345 is about 639.2613100019.

The spelling of 261237345 in words is "two hundred sixty-one million, two hundred thirty-seven thousand, three hundred forty-five".