7923421 has 4 divisors (see below), whose sum is σ = 8643744. Its totient is φ = 7203100.

The previous prime is 7923397. The next prime is 7923427. The reversal of 7923421 is 1243297.

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: 1243297 = 11 ⋅113027.

It is a cyclic number.

It is not a de Polignac number, because 7923421 - 2¹¹ = 7921373 is a prime.

It is a Duffinian number.

7923421 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 7923421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7923427) 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, 360145 + ... + 360166.

It is an arithmetic number, because the mean of its divisors is an integer number (2160936).

Almost surely, 2^7923421 is an apocalyptic number.

It is an amenable number.

7923421 is a deficient number, since it is larger than the sum of its proper divisors (720323).

7923421 is a wasteful number, since it uses less digits than its factorization.

7923421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 720322.

The product of its digits is 3024, while the sum is 28.

The square root of 7923421 is about 2814.8571899832. The cubic root of 7923421 is about 199.3597945381.

The spelling of 7923421 in words is "seven million, nine hundred twenty-three thousand, four hundred twenty-one".