8721243890 has 16 divisors (see below), whose sum is σ = 15699429720. Its totient is φ = 3488232960.

The previous prime is 8721243877. The next prime is 8721243917. The reversal of 8721243890 is 983421278.

It can be written as a sum of positive squares in 4 ways, for example, as 8704703401 + 16540489 = 93299^2 + 4067^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 157826 + ... + 205794.

Almost surely, 2^8721243890 is an apocalyptic number.

8721243890 is a deficient number, since it is larger than the sum of its proper divisors (6978185830).

8721243890 is a wasteful number, since it uses less digits than its factorization.

8721243890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66157.

The product of its (nonzero) digits is 193536, while the sum is 44.

The square root of 8721243890 is about 93387.6003011106. The cubic root of 8721243890 is about 2058.3827985220.

The spelling of 8721243890 in words is "eight billion, seven hundred twenty-one million, two hundred forty-three thousand, eight hundred ninety".