64312421 has 2 divisors, whose sum is σ = 64312422. Its totient is φ = 64312420.

The previous prime is 64312357. The next prime is 64312433. The reversal of 64312421 is 12421346.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 32615521 + 31696900 = 5711^2 + 5630^2 .

It is a cyclic number.

It is not a de Polignac number, because 64312421 - 2⁶ = 64312357 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64312441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32156210 + 32156211.

It is an arithmetic number, because the mean of its divisors is an integer number (32156211).

Almost surely, 2^64312421 is an apocalyptic number.

It is an amenable number.

64312421 is a deficient number, since it is larger than the sum of its proper divisors (1).

64312421 is an equidigital number, since it uses as much as digits as its factorization.

64312421 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 23.

The square root of 64312421 is about 8019.5025406817. The cubic root of 64312421 is about 400.6498208438.

Adding to 64312421 its reverse (12421346), we get a palindrome (76733767).

The spelling of 64312421 in words is "sixty-four million, three hundred twelve thousand, four hundred twenty-one".