21204143100 has 216 divisors, whose sum is σ = 76386360960. Its totient is φ = 4819328640.

The previous prime is 21204143099. The next prime is 21204143123. The reversal of 21204143100 is 134140212.

It is a super-2 number, since 2×21204143100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1118299 + ... + 1137101.

It is an arithmetic number, because the mean of its divisors is an integer number (353640560).

Almost surely, 2^21204143100 is an apocalyptic number.

21204143100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21204143100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38193180480).

21204143100 is an abundant number, since it is smaller than the sum of its proper divisors (55182217860).

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

21204143100 is a wasteful number, since it uses less digits than its factorization.

21204143100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19009 (or 18999 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21204143100 its reverse (134140212), we get a palindrome (21338283312).

The spelling of 21204143100 in words is "twenty-one billion, two hundred four million, one hundred forty-three thousand, one hundred".