664012549 has 2 divisors, whose sum is σ = 664012550. Its totient is φ = 664012548.

The previous prime is 664012499. The next prime is 664012577. The reversal of 664012549 is 945210466.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 662032900 + 1979649 = 25730^2 + 1407^2 .

It is a cyclic number.

It is not a de Polignac number, because 664012549 - 2¹³ = 664004357 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664012649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332006274 + 332006275.

It is an arithmetic number, because the mean of its divisors is an integer number (332006275).

Almost surely, 2^664012549 is an apocalyptic number.

It is an amenable number.

664012549 is a deficient number, since it is larger than the sum of its proper divisors (1).

664012549 is an equidigital number, since it uses as much as digits as its factorization.

664012549 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 37.

The square root of 664012549 is about 25768.4409501235. The cubic root of 664012549 is about 872.4196302026.

The spelling of 664012549 in words is "six hundred sixty-four million, twelve thousand, five hundred forty-nine".