64385821 has 2 divisors, whose sum is σ = 64385822. Its totient is φ = 64385820.

The previous prime is 64385807. The next prime is 64385833. The reversal of 64385821 is 12858346.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 57304900 + 7080921 = 7570^2 + 2661^2 .

It is a cyclic number.

It is not a de Polignac number, because 64385821 - 2⁷ = 64385693 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64385891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32192910 + 32192911.

It is an arithmetic number, because the mean of its divisors is an integer number (32192911).

Almost surely, 2^64385821 is an apocalyptic number.

It is an amenable number.

64385821 is a deficient number, since it is larger than the sum of its proper divisors (1).

64385821 is an equidigital number, since it uses as much as digits as its factorization.

64385821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 46080, while the sum is 37.

The square root of 64385821 is about 8024.0775793857. The cubic root of 64385821 is about 400.8021839269.

The spelling of 64385821 in words is "sixty-four million, three hundred eighty-five thousand, eight hundred twenty-one".