261857122 has 8 divisors (see below), whose sum is σ = 392942016. Its totient is φ = 130876452.

The previous prime is 261857111. The next prime is 261857147. The reversal of 261857122 is 221758162.

It is a happy number.

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19438 + ... + 30025.

It is an arithmetic number, because the mean of its divisors is an integer number (49117752).

Almost surely, 2^261857122 is an apocalyptic number.

261857122 is a deficient number, since it is larger than the sum of its proper divisors (131084894).

261857122 is a wasteful number, since it uses less digits than its factorization.

261857122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52112.

The product of its digits is 13440, while the sum is 34.

The square root of 261857122 is about 16181.9999382029. Note that the first 4 decimals coincide. The cubic root of 261857122 is about 639.7664528709.

The spelling of 261857122 in words is "two hundred sixty-one million, eight hundred fifty-seven thousand, one hundred twenty-two".