64424821 has 2 divisors, whose sum is σ = 64424822. Its totient is φ = 64424820.

The previous prime is 64424819. The next prime is 64424869. The reversal of 64424821 is 12842446.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 34939921 + 29484900 = 5911^2 + 5430^2 .

It is a cyclic number.

It is not a de Polignac number, because 64424821 - 2¹ = 64424819 is a prime.

Together with 64424819, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64424891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32212410 + 32212411.

It is an arithmetic number, because the mean of its divisors is an integer number (32212411).

Almost surely, 2^64424821 is an apocalyptic number.

It is an amenable number.

64424821 is a deficient number, since it is larger than the sum of its proper divisors (1).

64424821 is an equidigital number, since it uses as much as digits as its factorization.

64424821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 12288, while the sum is 31.

The square root of 64424821 is about 8026.5073973678. The cubic root of 64424821 is about 400.8830926835.

The spelling of 64424821 in words is "sixty-four million, four hundred twenty-four thousand, eight hundred twenty-one".