21987792071 has 8 divisors (see below), whose sum is σ = 25320729984. Its totient is φ = 18702810360.

The previous prime is 21987792007. The next prime is 21987792109. The reversal of 21987792071 is 17029778912.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21987792071 - 2⁶ = 21987792007 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21987692071) 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, 11988065 + ... + 11989898.

It is an arithmetic number, because the mean of its divisors is an integer number (3165091248).

Almost surely, 2^21987792071 is an apocalyptic number.

21987792071 is a deficient number, since it is larger than the sum of its proper divisors (3332937913).

21987792071 is a wasteful number, since it uses less digits than its factorization.

21987792071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23978101.

The product of its (nonzero) digits is 889056, while the sum is 53.

The spelling of 21987792071 in words is "twenty-one billion, nine hundred eighty-seven million, seven hundred ninety-two thousand, seventy-one".