261443151 has 12 divisors (see below), whose sum is σ = 380047512. Its totient is φ = 173184336.

The previous prime is 261443141. The next prime is 261443167. The reversal of 261443151 is 151344162.

It is a happy number.

261443151 is a `hidden beast` number, since 2 + 614 + 43 + 1 + 5 + 1 = 666.

It is not a de Polignac number, because 261443151 - 2⁷ = 261443023 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261443141) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 91101 + ... + 93926.

It is an arithmetic number, because the mean of its divisors is an integer number (31670626).

Almost surely, 2^261443151 is an apocalyptic number.

261443151 is a deficient number, since it is larger than the sum of its proper divisors (118604361).

261443151 is a wasteful number, since it uses less digits than its factorization.

261443151 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 185190 (or 185187 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 261443151 is about 16169.2037837365. The cubic root of 261443151 is about 639.4291385833.

The spelling of 261443151 in words is "two hundred sixty-one million, four hundred forty-three thousand, one hundred fifty-one".