40245721 has 8 divisors (see below), whose sum is σ = 41399424. Its totient is φ = 39102000.

The previous prime is 40245701. The next prime is 40245727. The reversal of 40245721 is 12754204.

40245721 is nontrivially palindromic in base 14.

40245721 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 a cyclic number.

It is not a de Polignac number, because 40245721 - 2¹⁷ = 40114649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (40245727) 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, 6096 + ... + 10846.

It is an arithmetic number, because the mean of its divisors is an integer number (5174928).

Almost surely, 2^40245721 is an apocalyptic number.

It is an amenable number.

40245721 is a deficient number, since it is larger than the sum of its proper divisors (1153703).

40245721 is a wasteful number, since it uses less digits than its factorization.

40245721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4991.

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 40245721 is about 6343.9515288186. The cubic root of 40245721 is about 342.6940552320.

Adding to 40245721 its reverse (12754204), we get a palindrome (52999925).

The spelling of 40245721 in words is "forty million, two hundred forty-five thousand, seven hundred twenty-one".