261839151 has 24 divisors (see below), whose sum is σ = 457670304. Its totient is φ = 140820480.

The previous prime is 261839093. The next prime is 261839159. The reversal of 261839151 is 151938162.

261839151 is a `hidden beast` number, since 2 + 618 + 39 + 1 + 5 + 1 = 666.

It is not a de Polignac number, because 261839151 - 2⁶ = 261839087 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261839159) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 121170 + ... + 123311.

It is an arithmetic number, because the mean of its divisors is an integer number (19069596).

Almost surely, 2^261839151 is an apocalyptic number.

261839151 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

261839151 is a deficient number, since it is larger than the sum of its proper divisors (195831153).

261839151 is a wasteful number, since it uses less digits than its factorization.

261839151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 244511 (or 244508 counting only the distinct ones).

The product of its digits is 12960, while the sum is 36.

The square root of 261839151 is about 16181.4446512047. Note that the first 3 decimals coincide. The cubic root of 261839151 is about 639.7518170193.

The spelling of 261839151 in words is "two hundred sixty-one million, eight hundred thirty-nine thousand, one hundred fifty-one".