213100020 has 216 divisors, whose sum is σ = 773443944. Its totient is φ = 47319552.

The previous prime is 213100009. The next prime is 213100061. The reversal of 213100020 is 20001312.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 33593616 + 179506404 = 5796^2 + 13398^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 213099975 and 213100011.

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, 326014 + ... + 326666.

It is an arithmetic number, because the mean of its divisors is an integer number (3580759).

Almost surely, 2^213100020 is an apocalyptic number.

213100020 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 213100020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (386721972).

213100020 is an abundant number, since it is smaller than the sum of its proper divisors (560343924).

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

213100020 is a wasteful number, since it uses less digits than its factorization.

213100020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 719 (or 707 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 213100020 is about 14597.9457458918. The cubic root of 213100020 is about 597.3027260250.

Adding to 213100020 its reverse (20001312), we get a palindrome (233101332).

The spelling of 213100020 in words is "two hundred thirteen million, one hundred thousand, twenty".