213021000 has 96 divisors (see below), whose sum is σ = 720041400. Its totient is φ = 56803200.

The previous prime is 213020993. The next prime is 213021001. The reversal of 213021000 is 120312.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 47692836 + 165328164 = 6906^2 + 12858^2 .

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

It is not an unprimeable number, because it can be changed into a prime (213021001) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2835 + ... + 20834.

Almost surely, 2^213021000 is an apocalyptic number.

213021000 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 213021000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (360020700).

213021000 is an abundant number, since it is smaller than the sum of its proper divisors (507020400).

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

213021000 is a wasteful number, since it uses less digits than its factorization.

213021000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23696 (or 23679 counting only the distinct ones).

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

The square root of 213021000 is about 14595.2389497397. The cubic root of 213021000 is about 597.2288879331.

Adding to 213021000 its reverse (120312), we get a palindrome (213141312).

The spelling of 213021000 in words is "two hundred thirteen million, twenty-one thousand".