21211313100 has 432 divisors, whose sum is σ = 70504299936. Its totient is φ = 4902912000.

The previous prime is 21211313099. The next prime is 21211313143. The reversal of 21211313100 is 131311212.

It is a happy number.

It is a super-2 number, since 2×21211313100² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21211313100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 75484960 + ... + 75485240.

It is an arithmetic number, because the mean of its divisors is an integer number (163204398).

Almost surely, 2^21211313100 is an apocalyptic number.

21211313100 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 21211313100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35252149968).

21211313100 is an abundant number, since it is smaller than the sum of its proper divisors (49292986836).

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

21211313100 is a wasteful number, since it uses less digits than its factorization.

21211313100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 394 (or 368 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 15.

Adding to 21211313100 its reverse (131311212), we get a palindrome (21342624312).

The spelling of 21211313100 in words is "twenty-one billion, two hundred eleven million, three hundred thirteen thousand, one hundred".