261871943 has 8 divisors (see below), whose sum is σ = 271296480. Its totient is φ = 252473760.

The previous prime is 261871931. The next prime is 261871957. The reversal of 261871943 is 349178162.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261871943 - 2¹⁶ = 261806407 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261871943.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261871843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14873 + ... + 27293.

It is an arithmetic number, because the mean of its divisors is an integer number (33912060).

Almost surely, 2^261871943 is an apocalyptic number.

261871943 is a deficient number, since it is larger than the sum of its proper divisors (9424537).

261871943 is a wasteful number, since it uses less digits than its factorization.

261871943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13177.

The product of its digits is 72576, while the sum is 41.

The square root of 261871943 is about 16182.4578788267. The cubic root of 261871943 is about 639.7785228115.

The spelling of 261871943 in words is "two hundred sixty-one million, eight hundred seventy-one thousand, nine hundred forty-three".