142221515 has 4 divisors (see below), whose sum is σ = 170665824. Its totient is φ = 113777208.

The previous prime is 142221509. The next prime is 142221529. The reversal of 142221515 is 515122241.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 515122241 = 43 ⋅11979587.

It is a cyclic number.

It is not a de Polignac number, because 142221515 - 2²⁰ = 141172939 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14222147 + ... + 14222156.

It is an arithmetic number, because the mean of its divisors is an integer number (42666456).

Almost surely, 2^142221515 is an apocalyptic number.

142221515 is a deficient number, since it is larger than the sum of its proper divisors (28444309).

142221515 is an equidigital number, since it uses as much as digits as its factorization.

142221515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28444308.

The product of its digits is 800, while the sum is 23.

The square root of 142221515 is about 11925.6662287689. Note that the first 3 decimals coincide. The cubic root of 142221515 is about 521.9814869415.

Adding to 142221515 its reverse (515122241), we get a palindrome (657343756).

It can be divided in two parts, 14222 and 1515, that multiplied together give a triangular number (21546330 = T₆₅₆₄).

The spelling of 142221515 in words is "one hundred forty-two million, two hundred twenty-one thousand, five hundred fifteen".