64621321 has 2 divisors, whose sum is σ = 64621322. Its totient is φ = 64621320.

The previous prime is 64621313. The next prime is 64621331. The reversal of 64621321 is 12312646.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41925625 + 22695696 = 6475^2 + 4764^2 .

It is a cyclic number.

It is not a de Polignac number, because 64621321 - 2³ = 64621313 is a prime.

It is not a weakly prime, because it can be changed into another prime (64621331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32310660 + 32310661.

It is an arithmetic number, because the mean of its divisors is an integer number (32310661).

Almost surely, 2^64621321 is an apocalyptic number.

It is an amenable number.

64621321 is a deficient number, since it is larger than the sum of its proper divisors (1).

64621321 is an equidigital number, since it uses as much as digits as its factorization.

64621321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1728, while the sum is 25.

The square root of 64621321 is about 8038.7387692349. The cubic root of 64621321 is about 401.2902523970.

Adding to 64621321 its reverse (12312646), we get a palindrome (76933967).

The spelling of 64621321 in words is "sixty-four million, six hundred twenty-one thousand, three hundred twenty-one".