215205442 has 4 divisors (see below), whose sum is σ = 322808166. Its totient is φ = 107602720.

The previous prime is 215205439. The next prime is 215205451. The reversal of 215205442 is 244502512.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 123409881 + 91795561 = 11109^2 + 9581^2 .

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 53801359 + ... + 53801362.

Almost surely, 2^215205442 is an apocalyptic number.

215205442 is a deficient number, since it is larger than the sum of its proper divisors (107602724).

215205442 is a wasteful number, since it uses less digits than its factorization.

215205442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107602723.

The product of its (nonzero) digits is 3200, while the sum is 25.

The square root of 215205442 is about 14669.8821399492. The cubic root of 215205442 is about 599.2633942047.

Adding to 215205442 its reverse (244502512), we get a palindrome (459707954).

It can be divided in two parts, 21520 and 5442, that added together give a palindrome (26962).

The spelling of 215205442 in words is "two hundred fifteen million, two hundred five thousand, four hundred forty-two".