261012599 has 4 divisors (see below), whose sum is σ = 263407320. Its totient is φ = 258617880.

The previous prime is 261012593. The next prime is 261012607. The reversal of 261012599 is 995210162.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261012599 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 (261012593) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1197197 + ... + 1197414.

It is an arithmetic number, because the mean of its divisors is an integer number (65851830).

Almost surely, 2^261012599 is an apocalyptic number.

261012599 is a deficient number, since it is larger than the sum of its proper divisors (2394721).

261012599 is a wasteful number, since it uses less digits than its factorization.

261012599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2394720.

The product of its (nonzero) digits is 9720, while the sum is 35.

The square root of 261012599 is about 16155.8843459589. The cubic root of 261012599 is about 639.0779357056.

The spelling of 261012599 in words is "two hundred sixty-one million, twelve thousand, five hundred ninety-nine".