40664321 has 2 divisors, whose sum is σ = 40664322. Its totient is φ = 40664320.

The previous prime is 40664287. The next prime is 40664347. The reversal of 40664321 is 12346604.

It is an a-pointer prime, because the next prime (40664347) can be obtained adding 40664321 to its sum of digits (26).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 34105600 + 6558721 = 5840^2 + 2561^2 .

It is a cyclic number.

It is not a de Polignac number, because 40664321 - 2¹⁰ = 40663297 is a prime.

It is equal to p_2471570 and since 40664321 and 2471570 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (40661321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20332160 + 20332161.

It is an arithmetic number, because the mean of its divisors is an integer number (20332161).

Almost surely, 2^40664321 is an apocalyptic number.

It is an amenable number.

40664321 is a deficient number, since it is larger than the sum of its proper divisors (1).

40664321 is an equidigital number, since it uses as much as digits as its factorization.

40664321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 40664321 is about 6376.8582389763. The cubic root of 40664321 is about 343.8780919435.

The spelling of 40664321 in words is "forty million, six hundred sixty-four thousand, three hundred twenty-one".