8721137 has 4 divisors (see below), whose sum is σ = 9002496. Its totient is φ = 8439780.

The previous prime is 8721121. The next prime is 8721157. The reversal of 8721137 is 7311278.

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.

It is a cyclic number.

It is not a de Polignac number, because 8721137 - 2⁴ = 8721121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8721157) 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, 140633 + ... + 140694.

It is an arithmetic number, because the mean of its divisors is an integer number (2250624).

Almost surely, 2^8721137 is an apocalyptic number.

It is an amenable number.

8721137 is a deficient number, since it is larger than the sum of its proper divisors (281359).

8721137 is a wasteful number, since it uses less digits than its factorization.

8721137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 281358.

The product of its digits is 2352, while the sum is 29.

The square root of 8721137 is about 2953.1571241639. The cubic root of 8721137 is about 205.8374389116.

The spelling of 8721137 in words is "eight million, seven hundred twenty-one thousand, one hundred thirty-seven".