64837891 has 2 divisors, whose sum is σ = 64837892. Its totient is φ = 64837890.

The previous prime is 64837889. The next prime is 64837909. The reversal of 64837891 is 19873846.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64837891 - 2¹ = 64837889 is a prime.

Together with 64837889, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (64837841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32418945 + 32418946.

It is an arithmetic number, because the mean of its divisors is an integer number (32418946).

Almost surely, 2^64837891 is an apocalyptic number.

64837891 is a deficient number, since it is larger than the sum of its proper divisors (1).

64837891 is an equidigital number, since it uses as much as digits as its factorization.

64837891 is an evil number, because the sum of its binary digits is even.

The product of its digits is 290304, while the sum is 46.

The square root of 64837891 is about 8052.1978987106. The cubic root of 64837891 is about 401.7380433254.

The spelling of 64837891 in words is "sixty-four million, eight hundred thirty-seven thousand, eight hundred ninety-one".