864140921 has 12 divisors (see below), whose sum is σ = 1005775488. Its totient is φ = 740286792.

The previous prime is 864140911. The next prime is 864140987. The reversal of 864140921 is 129041468.

It is a happy number.

It is not a de Polignac number, because 864140921 - 2¹⁰ = 864139897 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (864140911) 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 11 ways as a sum of consecutive naturals, for example, 116300 + ... + 123506.

It is an arithmetic number, because the mean of its divisors is an integer number (83814624).

Almost surely, 2^864140921 is an apocalyptic number.

It is an amenable number.

864140921 is a deficient number, since it is larger than the sum of its proper divisors (141634567).

864140921 is a wasteful number, since it uses less digits than its factorization.

864140921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9668 (or 9661 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 35.

The square root of 864140921 is about 29396.2739305511. The cubic root of 864140921 is about 952.4924103436.

The spelling of 864140921 in words is "eight hundred sixty-four million, one hundred forty thousand, nine hundred twenty-one".