8437921 has 4 divisors (see below), whose sum is σ = 8710144. Its totient is φ = 8165700.

The previous prime is 8437909. The next prime is 8437931. The reversal of 8437921 is 1297348.

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 8437921 - 2⁵ = 8437889 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8437901) 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, 136065 + ... + 136126.

It is an arithmetic number, because the mean of its divisors is an integer number (2177536).

Almost surely, 2^8437921 is an apocalyptic number.

It is an amenable number.

8437921 is a deficient number, since it is larger than the sum of its proper divisors (272223).

8437921 is a wasteful number, since it uses less digits than its factorization.

8437921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 272222.

The product of its digits is 12096, while the sum is 34.

The square root of 8437921 is about 2904.8099765733. The cubic root of 8437921 is about 203.5847071729.

The spelling of 8437921 in words is "eight million, four hundred thirty-seven thousand, nine hundred twenty-one".