213720100 has 72 divisors (see below), whose sum is σ = 511404768. Its totient is φ = 76876800.

The previous prime is 213720097. The next prime is 213720109. The reversal of 213720100 is 1027312.

It is a happy number.

It is a super-2 number, since 2×213720100² = 91352562288020000, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (213720109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 105699 + ... + 107701.

It is an arithmetic number, because the mean of its divisors is an integer number (7102844).

Almost surely, 2^213720100 is an apocalyptic number.

213720100 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 213720100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255702384).

213720100 is an abundant number, since it is smaller than the sum of its proper divisors (297684668).

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

213720100 is a wasteful number, since it uses less digits than its factorization.

213720100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2125 (or 2118 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 213720100 is about 14619.1689230271. The cubic root of 213720100 is about 597.8815102872.

Adding to 213720100 its reverse (1027312), we get a palindrome (214747412).

The spelling of 213720100 in words is "two hundred thirteen million, seven hundred twenty thousand, one hundred".