8140721 has 8 divisors (see below), whose sum is σ = 8611200. Its totient is φ = 7674480.

The previous prime is 8140711. The next prime is 8140763. The reversal of 8140721 is 1270418.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-8140721 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8140711) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3416 + ... + 5286.

It is an arithmetic number, because the mean of its divisors is an integer number (1076400).

Almost surely, 2^8140721 is an apocalyptic number.

It is an amenable number.

8140721 is a deficient number, since it is larger than the sum of its proper divisors (470479).

8140721 is a wasteful number, since it uses less digits than its factorization.

8140721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2119.

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

The square root of 8140721 is about 2853.1948759242. The cubic root of 8140721 is about 201.1658655814.

The spelling of 8140721 in words is "eight million, one hundred forty thousand, seven hundred twenty-one".