215022420 has 72 divisors (see below), whose sum is σ = 654020640. Its totient is φ = 57182400.

The previous prime is 215022407. The next prime is 215022427. The reversal of 215022420 is 24220512.

It is a super-2 number, since 2×215022420² = 92469282205312800, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 215022393 and 215022402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215022427) 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, 73995 + ... + 76845.

It is an arithmetic number, because the mean of its divisors is an integer number (9083620).

Almost surely, 2^215022420 is an apocalyptic number.

215022420 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 215022420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (327010320).

215022420 is an abundant number, since it is smaller than the sum of its proper divisors (438998220).

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

215022420 is a wasteful number, since it uses less digits than its factorization.

215022420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3285 (or 3280 counting only the distinct ones).

The product of its (nonzero) digits is 320, while the sum is 18.

The square root of 215022420 is about 14663.6427943400. The cubic root of 215022420 is about 599.0934643450.

Adding to 215022420 its reverse (24220512), we get a palindrome (239242932).

The spelling of 215022420 in words is "two hundred fifteen million, twenty-two thousand, four hundred twenty".