40609021 has 2 divisors, whose sum is σ = 40609022. Its totient is φ = 40609020.

The previous prime is 40609013. The next prime is 40609043. The reversal of 40609021 is 12090604.

It is an a-pointer prime, because the next prime (40609043) can be obtained adding 40609021 to its sum of digits (22).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 32936121 + 7672900 = 5739^2 + 2770^2 .

It is a cyclic number.

It is not a de Polignac number, because 40609021 - 2³ = 40609013 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 40608983 and 40609001.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40609321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20304510 + 20304511.

It is an arithmetic number, because the mean of its divisors is an integer number (20304511).

Almost surely, 2^40609021 is an apocalyptic number.

It is an amenable number.

40609021 is a deficient number, since it is larger than the sum of its proper divisors (1).

40609021 is an equidigital number, since it uses as much as digits as its factorization.

40609021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 40609021 is about 6372.5207728182. The cubic root of 40609021 is about 343.7221396263.

Adding to 40609021 its reverse (12090604), we get a palindrome (52699625).

The spelling of 40609021 in words is "forty million, six hundred nine thousand, twenty-one".