43712721 has 12 divisors (see below), whose sum is σ = 67997748. Its totient is φ = 26900064.

The previous prime is 43712717. The next prime is 43712731. The reversal of 43712721 is 12721734.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 13242321 + 30470400 = 3639^2 + 5520^2 .

It is not a de Polignac number, because 43712721 - 2² = 43712717 is a prime.

It is not an unprimeable number, because it can be changed into a prime (43712731) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 186690 + ... + 186923.

It is an arithmetic number, because the mean of its divisors is an integer number (5666479).

Almost surely, 2^43712721 is an apocalyptic number.

It is an amenable number.

43712721 is a deficient number, since it is larger than the sum of its proper divisors (24285027).

43712721 is a wasteful number, since it uses less digits than its factorization.

43712721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 373632 (or 373629 counting only the distinct ones).

The product of its digits is 2352, while the sum is 27.

The square root of 43712721 is about 6611.5596495834. The cubic root of 43712721 is about 352.2648257826.

The spelling of 43712721 in words is "forty-three million, seven hundred twelve thousand, seven hundred twenty-one".