40002421 has 2 divisors, whose sum is σ = 40002422. Its totient is φ = 40002420.

The previous prime is 40002379. The next prime is 40002433. The reversal of 40002421 is 12420004.

40002421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34939921 + 5062500 = 5911^2 + 2250^2 .

It is a cyclic number.

It is not a de Polignac number, because 40002421 - 2²⁵ = 6447989 is a prime.

It is a super-2 number, since 2×40002421² = 3200387371722482, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40002481) 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 as a sum of consecutive naturals, namely, 20001210 + 20001211.

It is an arithmetic number, because the mean of its divisors is an integer number (20001211).

Almost surely, 2^40002421 is an apocalyptic number.

It is an amenable number.

40002421 is a deficient number, since it is larger than the sum of its proper divisors (1).

40002421 is an equidigital number, since it uses as much as digits as its factorization.

40002421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 64, while the sum is 13.

The square root of 40002421 is about 6324.7467142962. The cubic root of 40002421 is about 342.0020889491.

Adding to 40002421 its reverse (12420004), we get a palindrome (52422425).

The spelling of 40002421 in words is "forty million, two thousand, four hundred twenty-one".