261892849 has 4 divisors (see below), whose sum is σ = 262033380. Its totient is φ = 261752320.

The previous prime is 261892831. The next prime is 261892853. The reversal of 261892849 is 948298162.

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

It can be written as a sum of positive squares in 2 ways, for example, as 72335025 + 189557824 = 8505^2 + 13768^2 .

It is a cyclic number.

It is not a de Polignac number, because 261892849 - 2⁵ = 261892817 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261892889) 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, 67432 + ... + 71209.

It is an arithmetic number, because the mean of its divisors is an integer number (65508345).

Almost surely, 2^261892849 is an apocalyptic number.

It is an amenable number.

261892849 is a deficient number, since it is larger than the sum of its proper divisors (140531).

261892849 is a wasteful number, since it uses less digits than its factorization.

261892849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140530.

The product of its digits is 497664, while the sum is 49.

The square root of 261892849 is about 16183.1038123099. The cubic root of 261892849 is about 639.7955474861.

The spelling of 261892849 in words is "two hundred sixty-one million, eight hundred ninety-two thousand, eight hundred forty-nine".