40450021 has 4 divisors (see below), whose sum is σ = 42829452. Its totient is φ = 38070592.

The previous prime is 40449989. The next prime is 40450027. The reversal of 40450021 is 12005404.

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 17313921 + 23136100 = 4161^2 + 4810^2 .

It is a cyclic number.

It is not a de Polignac number, because 40450021 - 2⁵ = 40449989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40449977 and 40450004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40450027) 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, 1189690 + ... + 1189723.

It is an arithmetic number, because the mean of its divisors is an integer number (10707363).

Almost surely, 2^40450021 is an apocalyptic number.

It is an amenable number.

40450021 is a deficient number, since it is larger than the sum of its proper divisors (2379431).

40450021 is a wasteful number, since it uses less digits than its factorization.

40450021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2379430.

The product of its (nonzero) digits is 160, while the sum is 16.

The square root of 40450021 is about 6360.0330973982. The cubic root of 40450021 is about 343.2729512270.

Adding to 40450021 its reverse (12005404), we get a palindrome (52455425).

The spelling of 40450021 in words is "forty million, four hundred fifty thousand, twenty-one".