21204541100 has 36 divisors (see below), whose sum is σ = 46289422704. Its totient is φ = 8431020480.

The previous prime is 21204541097. The next prime is 21204541121. The reversal of 21204541100 is 114540212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (20).

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, 618167 + ... + 651566.

Almost surely, 2^21204541100 is an apocalyptic number.

21204541100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21204541100 is an abundant number, since it is smaller than the sum of its proper divisors (25084881604).

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

21204541100 is a wasteful number, since it uses less digits than its factorization.

21204541100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1269914 (or 1269907 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 20.

The spelling of 21204541100 in words is "twenty-one billion, two hundred four million, five hundred forty-one thousand, one hundred".