64811647 has 2 divisors, whose sum is σ = 64811648. Its totient is φ = 64811646.

The previous prime is 64811639. The next prime is 64811657. The reversal of 64811647 is 74611846.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 64811647 - 2³ = 64811639 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64811627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32405823 + 32405824.

It is an arithmetic number, because the mean of its divisors is an integer number (32405824).

Almost surely, 2^64811647 is an apocalyptic number.

64811647 is a deficient number, since it is larger than the sum of its proper divisors (1).

64811647 is an equidigital number, since it uses as much as digits as its factorization.

64811647 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 32256, while the sum is 37.

The square root of 64811647 is about 8050.5681165990. The cubic root of 64811647 is about 401.6838330693.

It can be divided in two parts, 6481 and 1647, that added together give a triangular number (8128 = T₁₂₇).

The spelling of 64811647 in words is "sixty-four million, eight hundred eleven thousand, six hundred forty-seven".