8721149 has 4 divisors (see below), whose sum is σ = 8727264. Its totient is φ = 8715036.

The previous prime is 8721121. The next prime is 8721157. The reversal of 8721149 is 9411278.

8721149 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-8721149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8721049) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 344 + ... + 4190.

It is an arithmetic number, because the mean of its divisors is an integer number (2181816).

Almost surely, 2^8721149 is an apocalyptic number.

It is an amenable number.

8721149 is a deficient number, since it is larger than the sum of its proper divisors (6115).

8721149 is a wasteful number, since it uses less digits than its factorization.

8721149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6114.

The product of its digits is 4032, while the sum is 32.

The square root of 8721149 is about 2953.1591558871. The cubic root of 8721149 is about 205.8375333201.

The spelling of 8721149 in words is "eight million, seven hundred twenty-one thousand, one hundred forty-nine".