261081886 has 32 divisors (see below), whose sum is σ = 452269440. Its totient is φ = 111960576.

The previous prime is 261081881. The next prime is 261081943. The reversal of 261081886 is 688180162.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261081881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31180 + ... + 38656.

It is an arithmetic number, because the mean of its divisors is an integer number (14133420).

Almost surely, 2^261081886 is an apocalyptic number.

261081886 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

261081886 is a deficient number, since it is larger than the sum of its proper divisors (191187554).

261081886 is a wasteful number, since it uses less digits than its factorization.

261081886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7588.

The product of its (nonzero) digits is 36864, while the sum is 40.

The square root of 261081886 is about 16158.0285307336. The cubic root of 261081886 is about 639.1344794326.

The spelling of 261081886 in words is "two hundred sixty-one million, eighty-one thousand, eight hundred eighty-six".