261854159 has 4 divisors (see below), whose sum is σ = 299261904. Its totient is φ = 224446416.

The previous prime is 261854147. The next prime is 261854191. The reversal of 261854159 is 951458162.

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 261854159 - 2⁸ = 261853903 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 (261854059) 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, 18703862 + ... + 18703875.

It is an arithmetic number, because the mean of its divisors is an integer number (74815476).

Almost surely, 2^261854159 is an apocalyptic number.

261854159 is a deficient number, since it is larger than the sum of its proper divisors (37407745).

261854159 is an equidigital number, since it uses as much as digits as its factorization.

261854159 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37407744.

The product of its digits is 86400, while the sum is 41.

The square root of 261854159 is about 16181.9083856015. The cubic root of 261854159 is about 639.7640398054.

The spelling of 261854159 in words is "two hundred sixty-one million, eight hundred fifty-four thousand, one hundred fifty-nine".