21980419917 has 8 divisors (see below), whose sum is σ = 29308079520. Its totient is φ = 14653186800.

The previous prime is 21980419871. The next prime is 21980419997. The reversal of 21980419917 is 71991408912.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21980419917 - 2²⁰ = 21979371341 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21980419917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21980419997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44059 + ... + 214247.

It is an arithmetic number, because the mean of its divisors is an integer number (3663509940).

Almost surely, 2^21980419917 is an apocalyptic number.

It is an amenable number.

21980419917 is a deficient number, since it is larger than the sum of its proper divisors (7327659603).

21980419917 is a wasteful number, since it uses less digits than its factorization.

21980419917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213243.

The product of its (nonzero) digits is 326592, while the sum is 51.

The spelling of 21980419917 in words is "twenty-one billion, nine hundred eighty million, four hundred nineteen thousand, nine hundred seventeen".