423015721 has 4 divisors (see below), whose sum is σ = 437602500. Its totient is φ = 408428944.

The previous prime is 423015707. The next prime is 423015731. The reversal of 423015721 is 127510324.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 280093696 + 142922025 = 16736^2 + 11955^2 .

It is a cyclic number.

It is not a de Polignac number, because 423015721 - 2²¹ = 420918569 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (423015731) 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, 7293346 + ... + 7293403.

It is an arithmetic number, because the mean of its divisors is an integer number (109400625).

Almost surely, 2^423015721 is an apocalyptic number.

It is an amenable number.

423015721 is a deficient number, since it is larger than the sum of its proper divisors (14586779).

423015721 is a wasteful number, since it uses less digits than its factorization.

423015721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14586778.

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 423015721 is about 20567.3459882407. The cubic root of 423015721 is about 750.6753744580.

The spelling of 423015721 in words is "four hundred twenty-three million, fifteen thousand, seven hundred twenty-one".