43725721 has 8 divisors (see below), whose sum is σ = 48238344. Its totient is φ = 39377280.

The previous prime is 43725713. The next prime is 43725727. The reversal of 43725721 is 12752734.

It can be written as a sum of positive squares in 4 ways, for example, as 8620096 + 35105625 = 2936^2 + 5925^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 43725721 - 2³ = 43725713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (43725727) 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, 40486 + ... + 41551.

It is an arithmetic number, because the mean of its divisors is an integer number (6029793).

Almost surely, 2^43725721 is an apocalyptic number.

43725721 is a gapful number since it is divisible by the number (41) formed by its first and last digit.

It is an amenable number.

43725721 is a deficient number, since it is larger than the sum of its proper divisors (4512623).

43725721 is a wasteful number, since it uses less digits than its factorization.

43725721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82091.

The product of its digits is 11760, while the sum is 31.

The square root of 43725721 is about 6612.5427030757. The cubic root of 43725721 is about 352.2997430693.

The spelling of 43725721 in words is "forty-three million, seven hundred twenty-five thousand, seven hundred twenty-one".