261513607 has 4 divisors (see below), whose sum is σ = 266447880. Its totient is φ = 256579336.

The previous prime is 261513559. The next prime is 261513631. The reversal of 261513607 is 706315162.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 261513607 - 2²³ = 253124999 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261513647) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2467057 + ... + 2467162.

It is an arithmetic number, because the mean of its divisors is an integer number (66611970).

Almost surely, 2^261513607 is an apocalyptic number.

261513607 is a deficient number, since it is larger than the sum of its proper divisors (4934273).

261513607 is an equidigital number, since it uses as much as digits as its factorization.

261513607 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4934272.

The product of its (nonzero) digits is 7560, while the sum is 31.

The square root of 261513607 is about 16171.3823466023. The cubic root of 261513607 is about 639.4865730872.

Adding to 261513607 its reverse (706315162), we get a palindrome (967828769).

The spelling of 261513607 in words is "two hundred sixty-one million, five hundred thirteen thousand, six hundred seven".