43842721 has 8 divisors (see below), whose sum is σ = 47518184. Its totient is φ = 40210560.

The previous prime is 43842719. The next prime is 43842731. The reversal of 43842721 is 12724834.

It can be written as a sum of positive squares in 4 ways, for example, as 1852321 + 41990400 = 1361^2 + 6480^2 .

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

It is not a de Polignac number, because 43842721 - 2¹ = 43842719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43842731) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8700 + ... + 12781.

It is an arithmetic number, because the mean of its divisors is an integer number (5939773).

Almost surely, 2^43842721 is an apocalyptic number.

It is an amenable number.

43842721 is a deficient number, since it is larger than the sum of its proper divisors (3675463).

43842721 is a wasteful number, since it uses less digits than its factorization.

43842721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21651.

The product of its digits is 10752, while the sum is 31.

The square root of 43842721 is about 6621.3836167375. The cubic root of 43842721 is about 352.6136876561.

The spelling of 43842721 in words is "forty-three million, eight hundred forty-two thousand, seven hundred twenty-one".