40424821 has 2 divisors, whose sum is σ = 40424822. Its totient is φ = 40424820.

The previous prime is 40424819. The next prime is 40424833. The reversal of 40424821 is 12842404.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 37075921 + 3348900 = 6089^2 + 1830^2 .

It is a cyclic number.

It is not a de Polignac number, because 40424821 - 2¹ = 40424819 is a prime.

Together with 40424819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40424851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20212410 + 20212411.

It is an arithmetic number, because the mean of its divisors is an integer number (20212411).

Almost surely, 2^40424821 is an apocalyptic number.

It is an amenable number.

40424821 is a deficient number, since it is larger than the sum of its proper divisors (1).

40424821 is an equidigital number, since it uses as much as digits as its factorization.

40424821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2048, while the sum is 25.

The square root of 40424821 is about 6358.0516669810. The cubic root of 40424821 is about 343.2016510961.

The spelling of 40424821 in words is "forty million, four hundred twenty-four thousand, eight hundred twenty-one".