64644031 has 2 divisors, whose sum is σ = 64644032. Its totient is φ = 64644030.

The previous prime is 64644029. The next prime is 64644043. The reversal of 64644031 is 13044646.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64644031 - 2¹ = 64644029 is a prime.

It is a super-2 number, since 2×64644031² = 8357701487857922, which contains 22 as substring.

Together with 64644029, 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 (64644011) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32322015 + 32322016.

It is an arithmetic number, because the mean of its divisors is an integer number (32322016).

Almost surely, 2^64644031 is an apocalyptic number.

64644031 is a deficient number, since it is larger than the sum of its proper divisors (1).

64644031 is an equidigital number, since it uses as much as digits as its factorization.

64644031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 64644031 is about 8040.1511801707. The cubic root of 64644031 is about 401.3372556364.

Adding to 64644031 its reverse (13044646), we get a palindrome (77688677).

The spelling of 64644031 in words is "sixty-four million, six hundred forty-four thousand, thirty-one".