21987696206 has 12 divisors (see below), whose sum is σ = 38366286408. Its totient is φ = 9423298332.

The previous prime is 21987696169. The next prime is 21987696217. The reversal of 21987696206 is 60269678912.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 112182026 + ... + 112182221.

It is an arithmetic number, because the mean of its divisors is an integer number (3197190534).

Almost surely, 2^21987696206 is an apocalyptic number.

21987696206 is a deficient number, since it is larger than the sum of its proper divisors (16378590202).

21987696206 is a wasteful number, since it uses less digits than its factorization.

21987696206 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 224364263 (or 224364256 counting only the distinct ones).

The product of its (nonzero) digits is 3919104, while the sum is 56.

The spelling of 21987696206 in words is "twenty-one billion, nine hundred eighty-seven million, six hundred ninety-six thousand, two hundred six".