581681261 has 8 divisors (see below), whose sum is σ = 665201664. Its totient is φ = 498266640.

The previous prime is 581681183. The next prime is 581681263. The reversal of 581681261 is 162186185.

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 581681261 - 2¹⁸ = 581419117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (581681263) 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, 14285 + ... + 36978.

It is an arithmetic number, because the mean of its divisors is an integer number (83150208).

Almost surely, 2^581681261 is an apocalyptic number.

It is an amenable number.

581681261 is a deficient number, since it is larger than the sum of its proper divisors (83520403).

581681261 is a wasteful number, since it uses less digits than its factorization.

581681261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52891.

The product of its digits is 23040, while the sum is 38.

The square root of 581681261 is about 24118.0691805957. The cubic root of 581681261 is about 834.7601165888.

The spelling of 581681261 in words is "five hundred eighty-one million, six hundred eighty-one thousand, two hundred sixty-one".