40800021 has 4 divisors (see below), whose sum is σ = 54400032. Its totient is φ = 27200012.

The previous prime is 40799989. The next prime is 40800073. The reversal of 40800021 is 12000804.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40800021 - 2⁵ = 40799989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40800121) 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, 6800001 + ... + 6800006.

It is an arithmetic number, because the mean of its divisors is an integer number (13600008).

Almost surely, 2^40800021 is an apocalyptic number.

It is an amenable number.

40800021 is a deficient number, since it is larger than the sum of its proper divisors (13600011).

40800021 is a wasteful number, since it uses less digits than its factorization.

40800021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13600010.

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 40800021 is about 6387.4894129071. The cubic root of 40800021 is about 344.2601832095.

Adding to 40800021 its reverse (12000804), we get a palindrome (52800825).

The spelling of 40800021 in words is "forty million, eight hundred thousand, twenty-one".