21247945876 has 12 divisors (see below), whose sum is σ = 37251887008. Its totient is φ = 10604549592.

The previous prime is 21247945861. The next prime is 21247945889. The reversal of 21247945876 is 67854974212.

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, 4853376 + ... + 4857751.

Almost surely, 2^21247945876 is an apocalyptic number.

It is an amenable number.

21247945876 is a deficient number, since it is larger than the sum of its proper divisors (16003941132).

21247945876 is a wasteful number, since it uses less digits than its factorization.

21247945876 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9711678 (or 9711676 counting only the distinct ones).

The product of its digits is 6773760, while the sum is 55.

The spelling of 21247945876 in words is "twenty-one billion, two hundred forty-seven million, nine hundred forty-five thousand, eight hundred seventy-six".