21178947476 has 12 divisors (see below), whose sum is σ = 37107339360. Its totient is φ = 10576850520.

The previous prime is 21178947373. The next prime is 21178947481. The reversal of 21178947476 is 67474987112.

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, 3152030 + ... + 3158741.

It is an arithmetic number, because the mean of its divisors is an integer number (3092278280).

Almost surely, 2^21178947476 is an apocalyptic number.

It is an amenable number.

21178947476 is a deficient number, since it is larger than the sum of its proper divisors (15928391884).

21178947476 is a wasteful number, since it uses less digits than its factorization.

21178947476 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6311614 (or 6311612 counting only the distinct ones).

The product of its digits is 4741632, while the sum is 56.

The spelling of 21178947476 in words is "twenty-one billion, one hundred seventy-eight million, nine hundred forty-seven thousand, four hundred seventy-six".