42723921 has 8 divisors (see below), whose sum is σ = 58802944. Its totient is φ = 27563760.

The previous prime is 42723917. The next prime is 42723929. The reversal of 42723921 is 12932724.

42723921 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is not a de Polignac number, because 42723921 - 2² = 42723917 is a prime.

It is a super-2 number, since 2×42723921² = 3650666851228482, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42723929) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 229606 + ... + 229791.

It is an arithmetic number, because the mean of its divisors is an integer number (7350368).

Almost surely, 2^42723921 is an apocalyptic number.

It is an amenable number.

42723921 is a deficient number, since it is larger than the sum of its proper divisors (16079023).

42723921 is a wasteful number, since it uses less digits than its factorization.

42723921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 459431.

The product of its digits is 6048, while the sum is 30.

The square root of 42723921 is about 6536.3538000937. The cubic root of 42723921 is about 349.5884168681.

The spelling of 42723921 in words is "forty-two million, seven hundred twenty-three thousand, nine hundred twenty-one".