215212320 has 144 divisors (see below), whose sum is σ = 742053312. Its totient is φ = 56793600.

The previous prime is 215212279. The next prime is 215212337. The reversal of 215212320 is 23212512.

It is a tau number, because it is divible by the number of its divisors (144).

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 = 215212293 and 215212302.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 147595 + ... + 149045.

It is an arithmetic number, because the mean of its divisors is an integer number (5153148).

Almost surely, 2^215212320 is an apocalyptic number.

215212320 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 215212320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (371026656).

215212320 is an abundant number, since it is smaller than the sum of its proper divisors (526840992).

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

215212320 is a wasteful number, since it uses less digits than its factorization.

215212320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1575 (or 1564 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 215212320 is about 14670.1165639541. The cubic root of 215212320 is about 599.2697783210.

Adding to 215212320 its reverse (23212512), we get a palindrome (238424832).

The spelling of 215212320 in words is "two hundred fifteen million, two hundred twelve thousand, three hundred twenty".