21202012100 has 36 divisors (see below), whose sum is σ = 46590768000. Its totient is φ = 8373449760.

The previous prime is 21202012037. The next prime is 21202012121. The reversal of 21202012100 is 121020212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1334000 + ... + 1349799.

It is an arithmetic number, because the mean of its divisors is an integer number (1294188000).

Almost surely, 2^21202012100 is an apocalyptic number.

21202012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21202012100 is an abundant number, since it is smaller than the sum of its proper divisors (25388755900).

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

21202012100 is a wasteful number, since it uses less digits than its factorization.

21202012100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2683892 (or 2683885 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21202012100 its reverse (121020212), we get a palindrome (21323032312).

The spelling of 21202012100 in words is "twenty-one billion, two hundred two million, twelve thousand, one hundred".