40912021 has 2 divisors, whose sum is σ = 40912022. Its totient is φ = 40912020.

The previous prime is 40912019. The next prime is 40912051. The reversal of 40912021 is 12021904.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39564100 + 1347921 = 6290^2 + 1161^2 .

It is a cyclic number.

It is not a de Polignac number, because 40912021 - 2¹ = 40912019 is a prime.

Together with 40912019, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 40912021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40912051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20456010 + 20456011.

It is an arithmetic number, because the mean of its divisors is an integer number (20456011).

Almost surely, 2^40912021 is an apocalyptic number.

It is an amenable number.

40912021 is a deficient number, since it is larger than the sum of its proper divisors (1).

40912021 is an equidigital number, since it uses as much as digits as its factorization.

40912021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 40912021 is about 6396.2505423099. The cubic root of 40912021 is about 344.5749045606.

Adding to 40912021 its reverse (12021904), we get a palindrome (52933925).

The spelling of 40912021 in words is "forty million, nine hundred twelve thousand, twenty-one".