21100722828 has 48 divisors (see below), whose sum is σ = 50953980000. Its totient is φ = 6788210688.

The previous prime is 21100722757. The next prime is 21100722869. The reversal of 21100722828 is 82822700112.

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 15 ways as a sum of consecutive naturals, for example, 924498 + ... + 947046.

It is an arithmetic number, because the mean of its divisors is an integer number (1061541250).

Almost surely, 2^21100722828 is an apocalyptic number.

It is an amenable number.

21100722828 is an abundant number, since it is smaller than the sum of its proper divisors (29853257172).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21100722828 is a wasteful number, since it uses less digits than its factorization.

21100722828 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25274 (or 25272 counting only the distinct ones).

The product of its (nonzero) digits is 7168, while the sum is 33.

The spelling of 21100722828 in words is "twenty-one billion, one hundred million, seven hundred twenty-two thousand, eight hundred twenty-eight".