65787336221 has 4 divisors (see below), whose sum is σ = 66043318332. Its totient is φ = 65531354112.

The previous prime is 65787336169. The next prime is 65787336227. The reversal of 65787336221 is 12263378756.

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 42389044996 + 23398291225 = 205886^2 + 152965^2 .

It is a cyclic number.

It is not a de Polignac number, because 65787336221 - 2²² = 65783141917 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 65787336221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65787336227) 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 in 3 ways as a sum of consecutive naturals, for example, 127990670 + ... + 127991183.

It is an arithmetic number, because the mean of its divisors is an integer number (16510829583).

Almost surely, 2^65787336221 is an apocalyptic number.

It is an amenable number.

65787336221 is a deficient number, since it is larger than the sum of its proper divisors (255982111).

65787336221 is a wasteful number, since it uses less digits than its factorization.

65787336221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 255982110.

The product of its digits is 2540160, while the sum is 50.

The spelling of 65787336221 in words is "sixty-five billion, seven hundred eighty-seven million, three hundred thirty-six thousand, two hundred twenty-one".