215221142 has 4 divisors (see below), whose sum is σ = 322831716. Its totient is φ = 107610570.

The previous prime is 215221141. The next prime is 215221159. The reversal of 215221142 is 241122512.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215221141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53805284 + ... + 53805287.

It is an arithmetic number, because the mean of its divisors is an integer number (80707929).

Almost surely, 2^215221142 is an apocalyptic number.

215221142 is a deficient number, since it is larger than the sum of its proper divisors (107610574).

215221142 is a wasteful number, since it uses less digits than its factorization.

215221142 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 107610573.

The product of its digits is 320, while the sum is 20.

The square root of 215221142 is about 14670.4172401469. The cubic root of 215221142 is about 599.2779666468.

Adding to 215221142 its reverse (241122512), we get a palindrome (456343654).

The spelling of 215221142 in words is "two hundred fifteen million, two hundred twenty-one thousand, one hundred forty-two".