215242400 has 72 divisors (see below), whose sum is σ = 530333244. Its totient is φ = 85299200.

The previous prime is 215242369. The next prime is 215242403. The reversal of 215242400 is 4242512.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 795664 + 214446736 = 892^2 + 14644^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (215242403) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 89210 + ... + 91590.

Almost surely, 2^215242400 is an apocalyptic number.

215242400 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 215242400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (265166622).

215242400 is an abundant number, since it is smaller than the sum of its proper divisors (315090844).

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

215242400 is a wasteful number, since it uses less digits than its factorization.

215242400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2514 (or 2501 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 20.

The square root of 215242400 is about 14671.1417415278. The cubic root of 215242400 is about 599.2976967896.

Adding to 215242400 its reverse (4242512), we get a palindrome (219484912).

The spelling of 215242400 in words is "two hundred fifteen million, two hundred forty-two thousand, four hundred".