64646443 has 2 divisors, whose sum is σ = 64646444. Its totient is φ = 64646442.

The previous prime is 64646431. The next prime is 64646453. The reversal of 64646443 is 34464646.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 64646443 - 2¹³ = 64638251 is a prime.

It is not a weakly prime, because it can be changed into another prime (64646453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32323221 + 32323222.

It is an arithmetic number, because the mean of its divisors is an integer number (32323222).

Almost surely, 2^64646443 is an apocalyptic number.

64646443 is a deficient number, since it is larger than the sum of its proper divisors (1).

64646443 is an equidigital number, since it uses as much as digits as its factorization.

64646443 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165888, while the sum is 37.

The square root of 64646443 is about 8040.3011759511. The cubic root of 64646443 is about 401.3422471435.

It can be divided in two parts, 646 and 46443, that added together give a square (47089 = 217²).

The spelling of 64646443 in words is "sixty-four million, six hundred forty-six thousand, four hundred forty-three".