864261 has 12 divisors (see below), whose sum is σ = 1261260. Its totient is φ = 570240.

The previous prime is 864251. The next prime is 864277. The reversal of 864261 is 162468.

It can be written as a sum of positive squares in 2 ways, for example, as 367236 + 497025 = 606^2 + 705^2 .

It is not a de Polignac number, because 864261 - 2⁹ = 863749 is a prime.

It is a super-2 number, since 2×864261² = 1493894152242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (864211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 541 + ... + 1421.

It is an arithmetic number, because the mean of its divisors is an integer number (105105).

2⁸⁶⁴²⁶¹ is an apocalyptic number.

It is an amenable number.

864261 is a deficient number, since it is larger than the sum of its proper divisors (396999).

864261 is a wasteful number, since it uses less digits than its factorization.

864261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 996 (or 993 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 864261 is about 929.6563881349. The cubic root of 864261 is about 95.2536527006.

The spelling of 864261 in words is "eight hundred sixty-four thousand, two hundred sixty-one".