8721156 has 24 divisors (see below), whose sum is σ = 20488384. Its totient is φ = 2887200.

The previous prime is 8721121. The next prime is 8721157. The reversal of 8721156 is 6511278.

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (8721157) 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 7 ways as a sum of consecutive naturals, for example, 595 + ... + 4218.

Almost surely, 2^8721156 is an apocalyptic number.

It is an amenable number.

8721156 is an abundant number, since it is smaller than the sum of its proper divisors (11767228).

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

8721156 is a wasteful number, since it uses less digits than its factorization.

8721156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4971 (or 4969 counting only the distinct ones).

The product of its digits is 3360, while the sum is 30.

The square root of 8721156 is about 2953.1603410584. The cubic root of 8721156 is about 205.8375883917.

The spelling of 8721156 in words is "eight million, seven hundred twenty-one thousand, one hundred fifty-six".