8640261 has 12 divisors (see below), whose sum is σ = 14263392. Its totient is φ = 4937256.

The previous prime is 8640259. The next prime is 8640263. The reversal of 8640261 is 1620468.

It is an interprime number because it is at equal distance from previous prime (8640259) and next prime (8640263).

It is not a de Polignac number, because 8640261 - 2¹ = 8640259 is a prime.

It is a super-2 number, since 2×8640261² = 149308220296242, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8640263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 68511 + ... + 68636.

It is an arithmetic number, because the mean of its divisors is an integer number (1188616).

Almost surely, 2^8640261 is an apocalyptic number.

It is an amenable number.

8640261 is a deficient number, since it is larger than the sum of its proper divisors (5623131).

8640261 is a wasteful number, since it uses less digits than its factorization.

8640261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 137160 (or 137157 counting only the distinct ones).

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

The square root of 8640261 is about 2939.4320880061. The cubic root of 8640261 is about 205.1991798013.

The spelling of 8640261 in words is "eight million, six hundred forty thousand, two hundred sixty-one".