21995976788 has 12 divisors (see below), whose sum is σ = 38562070932. Its totient is φ = 10978242240.

The previous prime is 21995976773. The next prime is 21995976803. The reversal of 21995976788 is 88767959912.

It is an interprime number because it is at equal distance from previous prime (21995976773) and next prime (21995976803).

It can be written as a sum of positive squares in 2 ways, for example, as 12929509264 + 9066467524 = 113708^2 + 95218^2 .

It is a congruent number.

It is an unprimeable number.

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, 4934033 + ... + 4938488.

It is an arithmetic number, because the mean of its divisors is an integer number (3213505911).

Almost surely, 2^21995976788 is an apocalyptic number.

It is an amenable number.

21995976788 is a deficient number, since it is larger than the sum of its proper divisors (16566094144).

21995976788 is a wasteful number, since it uses less digits than its factorization.

21995976788 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9873082 (or 9873080 counting only the distinct ones).

The product of its digits is 137168640, while the sum is 71.

The spelling of 21995976788 in words is "twenty-one billion, nine hundred ninety-five million, nine hundred seventy-six thousand, seven hundred eighty-eight".