423721428 has 24 divisors (see below), whose sum is σ = 1064736288. Its totient is φ = 130375776.

The previous prime is 423721393. The next prime is 423721439. The reversal of 423721428 is 824127324.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1357926 + ... + 1358237.

It is an arithmetic number, because the mean of its divisors is an integer number (44364012).

Almost surely, 2^423721428 is an apocalyptic number.

It is an amenable number.

423721428 is an abundant number, since it is smaller than the sum of its proper divisors (641014860).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

423721428 is a wasteful number, since it uses less digits than its factorization.

423721428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2716183 (or 2716181 counting only the distinct ones).

The product of its digits is 21504, while the sum is 33.

The square root of 423721428 is about 20584.4948444211. The cubic root of 423721428 is about 751.0925871205.

The spelling of 423721428 in words is "four hundred twenty-three million, seven hundred twenty-one thousand, four hundred twenty-eight".