75863817821 has 6 divisors (see below), whose sum is σ = 83387502366. Its totient is φ = 68967107000.

The previous prime is 75863817797. The next prime is 75863817829. The reversal of 75863817821 is 12871836857.

It can be written as a sum of positive squares in only one way, i.e., 73522322500 + 2341495321 = 271150^2 + 48389^2 .

It is a de Polignac number, because none of the positive numbers 2^k-75863817821 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75863817829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 313486730 + ... + 313486971.

It is an arithmetic number, because the mean of its divisors is an integer number (13897917061).

Almost surely, 2^75863817821 is an apocalyptic number.

It is an amenable number.

75863817821 is a deficient number, since it is larger than the sum of its proper divisors (7523684545).

75863817821 is a wasteful number, since it uses less digits than its factorization.

75863817821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626973723 (or 626973712 counting only the distinct ones).

The product of its digits is 4515840, while the sum is 56.

The spelling of 75863817821 in words is "seventy-five billion, eight hundred sixty-three million, eight hundred seventeen thousand, eight hundred twenty-one".