8721140 has 24 divisors (see below), whose sum is σ = 19111680. Its totient is φ = 3336608.

The previous prime is 8721121. The next prime is 8721157. The reversal of 8721140 is 411278.

It is a Harshad number since it is a multiple of its sum of digits (23).

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9020 + ... + 9939.

It is an arithmetic number, because the mean of its divisors is an integer number (796320).

Almost surely, 2^8721140 is an apocalyptic number.

It is an amenable number.

8721140 is an abundant number, since it is smaller than the sum of its proper divisors (10390540).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

8721140 is a wasteful number, since it uses less digits than its factorization.

8721140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18991 (or 18989 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 8721140 is about 2953.1576320948. The cubic root of 8721140 is about 205.8374625138.

The spelling of 8721140 in words is "eight million, seven hundred twenty-one thousand, one hundred forty".