212142420 has 144 divisors (see below), whose sum is σ = 743154048. Its totient is φ = 47980800.

The previous prime is 212142377. The next prime is 212142457. The reversal of 212142420 is 24241212.

212142420 is digitally balanced in base 3 and base 9, because in such bases it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (18).

212142420 is strictly pandigital in base 9.

It is a junction number, because it is equal to n+sod(n) for n = 212142393 and 212142402.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 126427 + ... + 128093.

It is an arithmetic number, because the mean of its divisors is an integer number (5160792).

Almost surely, 2^212142420 is an apocalyptic number.

212142420 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 212142420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (371577024).

212142420 is an abundant number, since it is smaller than the sum of its proper divisors (531011628).

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

212142420 is a wasteful number, since it uses less digits than its factorization.

212142420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1790 (or 1785 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 212142420 is about 14565.1096803285. The cubic root of 212142420 is about 596.4066898296.

Adding to 212142420 its reverse (24241212), we get a palindrome (236383632).

The spelling of 212142420 in words is "two hundred twelve million, one hundred forty-two thousand, four hundred twenty".