40421023021 has 2 divisors, whose sum is σ = 40421023022. Its totient is φ = 40421023020.

The previous prime is 40421023007. The next prime is 40421023043. The reversal of 40421023021 is 12032012404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 38622075625 + 1798947396 = 196525^2 + 42414^2 .

It is a cyclic number.

It is not a de Polignac number, because 40421023021 - 2¹¹ = 40421020973 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 40421023021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40421020021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20210511510 + 20210511511.

It is an arithmetic number, because the mean of its divisors is an integer number (20210511511).

Almost surely, 2^40421023021 is an apocalyptic number.

It is an amenable number.

40421023021 is a deficient number, since it is larger than the sum of its proper divisors (1).

40421023021 is an equidigital number, since it uses as much as digits as its factorization.

40421023021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 40421023021 its reverse (12032012404), we get a palindrome (52453035425).

The spelling of 40421023021 in words is "forty billion, four hundred twenty-one million, twenty-three thousand, twenty-one".