21050504668 has 24 divisors (see below), whose sum is σ = 36986632704. Its totient is φ = 10482931200.

The previous prime is 21050504653. The next prime is 21050504687. The reversal of 21050504668 is 86640505012.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4456548 + ... + 4461268.

It is an arithmetic number, because the mean of its divisors is an integer number (1541109696).

Almost surely, 2^21050504668 is an apocalyptic number.

It is an amenable number.

21050504668 is a deficient number, since it is larger than the sum of its proper divisors (15936128036).

21050504668 is a wasteful number, since it uses less digits than its factorization.

21050504668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8973 (or 8971 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 37.

The spelling of 21050504668 in words is "twenty-one billion, fifty million, five hundred four thousand, six hundred sixty-eight".