32406721 has 4 divisors (see below), whose sum is σ = 32469444. Its totient is φ = 32344000.

The previous prime is 32406719. The next prime is 32406733. The reversal of 32406721 is 12760423.

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 5574321 + 26832400 = 2361^2 + 5180^2 .

It is a cyclic number.

It is not a de Polignac number, because 32406721 - 2¹ = 32406719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (32406791) 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, 30580 + ... + 31621.

It is an arithmetic number, because the mean of its divisors is an integer number (8117361).

Almost surely, 2^32406721 is an apocalyptic number.

It is an amenable number.

32406721 is a deficient number, since it is larger than the sum of its proper divisors (62723).

32406721 is an equidigital number, since it uses as much as digits as its factorization.

32406721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62722.

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 32406721 is about 5692.6901373604. The cubic root of 32406721 is about 318.8196128364.

The spelling of 32406721 in words is "thirty-two million, four hundred six thousand, seven hundred twenty-one".