64819644090877 has 4 divisors (see below), whose sum is σ = 69805770559420. Its totient is φ = 59833517622336.

The previous prime is 64819644090847. The next prime is 64819644090917. The reversal of 64819644090877 is 77809044691846.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 30028273797636 + 34791370293241 = 5479806^2 + 5898421^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64819644090877 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64819644090847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2493063234252 + ... + 2493063234277.

It is an arithmetic number, because the mean of its divisors is an integer number (17451442639855).

Almost surely, 2^{64819644090877} is an apocalyptic number.

It is an amenable number.

64819644090877 is a deficient number, since it is larger than the sum of its proper divisors (4986126468543).

64819644090877 is a wasteful number, since it uses less digits than its factorization.

64819644090877 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4986126468542.

The product of its (nonzero) digits is 585252864, while the sum is 73.

The spelling of 64819644090877 in words is "sixty-four trillion, eight hundred nineteen billion, six hundred forty-four million, ninety thousand, eight hundred seventy-seven".