21101101028 has 48 divisors (see below), whose sum is σ = 42701952384. Its totient is φ = 8936524800.

The previous prime is 21101101027. The next prime is 21101101031. The reversal of 21101101028 is 82010110112.

It is a junction number, because it is equal to n+sod(n) for n = 21101100997 and 21101101015.

It is not an unprimeable number, because it can be changed into a prime (21101101027) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1898375 + ... + 1909457.

It is an arithmetic number, because the mean of its divisors is an integer number (889624008).

Almost surely, 2^21101101028 is an apocalyptic number.

21101101028 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

21101101028 is an abundant number, since it is smaller than the sum of its proper divisors (21600851356).

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

21101101028 is a wasteful number, since it uses less digits than its factorization.

21101101028 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11892 (or 11890 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 17.

The spelling of 21101101028 in words is "twenty-one billion, one hundred one million, one hundred one thousand, twenty-eight".