21821476117 has 16 divisors (see below), whose sum is σ = 26257653760. Its totient is φ = 17715473712.

The previous prime is 21821476109. The next prime is 21821476129. The reversal of 21821476117 is 71167412812.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21821476117 - 2³ = 21821476109 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 21821476117.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21821470117) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 618988 + ... + 653290.

It is an arithmetic number, because the mean of its divisors is an integer number (1641103360).

Almost surely, 2^21821476117 is an apocalyptic number.

It is an amenable number.

21821476117 is a deficient number, since it is larger than the sum of its proper divisors (4436177643).

21821476117 is a wasteful number, since it uses less digits than its factorization.

21821476117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39112.

The product of its digits is 37632, while the sum is 40.

Adding to 21821476117 its reverse (71167412812), we get a palindrome (92988888929).

The spelling of 21821476117 in words is "twenty-one billion, eight hundred twenty-one million, four hundred seventy-six thousand, one hundred seventeen".