8740021 has 4 divisors (see below), whose sum is σ = 8772544. Its totient is φ = 8707500.

The previous prime is 8740003. The next prime is 8740037. The reversal of 8740021 is 1200478.

8740021 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 an emirpimes, since its reverse is a distinct semiprime: 1200478 = 2 ⋅600239.

It is a cyclic number.

It is not a de Polignac number, because 8740021 - 2²³ = 351413 is a prime.

It is an Ulam number.

It is a Duffinian number.

8740021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 8739974 and 8740001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (8740321) 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, 15855 + ... + 16396.

It is an arithmetic number, because the mean of its divisors is an integer number (2193136).

Almost surely, 2^8740021 is an apocalyptic number.

It is an amenable number.

8740021 is a deficient number, since it is larger than the sum of its proper divisors (32523).

8740021 is a wasteful number, since it uses less digits than its factorization.

8740021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32522.

The product of its (nonzero) digits is 448, while the sum is 22.

The square root of 8740021 is about 2956.3526514947. The cubic root of 8740021 is about 205.9858993710.

Adding to 8740021 its reverse (1200478), we get a palindrome (9940499).

The spelling of 8740021 in words is "eight million, seven hundred forty thousand, twenty-one".