213122021100 has 144 divisors (see below), whose sum is σ = 625566627840. Its totient is φ = 56014675200.

The previous prime is 213122021087. The next prime is 213122021107. The reversal of 213122021100 is 1120221312.

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 213122021100.

It is not an unprimeable number, because it can be changed into a prime (213122021107) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6228639 + ... + 6262761.

Almost surely, 2^213122021100 is an apocalyptic number.

213122021100 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 213122021100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (312783313920).

213122021100 is an abundant number, since it is smaller than the sum of its proper divisors (412444606740).

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

213122021100 is a wasteful number, since it uses less digits than its factorization.

213122021100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34440 (or 34433 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 213122021100 its reverse (1120221312), we get a palindrome (214242242412).

The spelling of 213122021100 in words is "two hundred thirteen billion, one hundred twenty-two million, twenty-one thousand, one hundred".