261280831 has 16 divisors (see below), whose sum is σ = 305856000. Its totient is φ = 218563488.

The previous prime is 261280801. The next prime is 261280843. The reversal of 261280831 is 138082162.

It is a cyclic number.

It is not a de Polignac number, because 261280831 - 2¹¹ = 261278783 is a prime.

It is a super-2 number, since 2×261280831² = 136535345296101122, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 261280793 and 261280802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261280801) 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 15 ways as a sum of consecutive naturals, for example, 72060 + ... + 75598.

It is an arithmetic number, because the mean of its divisors is an integer number (19116000).

Almost surely, 2^261280831 is an apocalyptic number.

261280831 is a deficient number, since it is larger than the sum of its proper divisors (44575169).

261280831 is a wasteful number, since it uses less digits than its factorization.

261280831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3798.

The product of its (nonzero) digits is 4608, while the sum is 31.

The square root of 261280831 is about 16164.1835859409. The cubic root of 261280831 is about 639.2967788651.

The spelling of 261280831 in words is "two hundred sixty-one million, two hundred eighty thousand, eight hundred thirty-one".