142440217 has 2 divisors, whose sum is σ = 142440218. Its totient is φ = 142440216.

The previous prime is 142440211. The next prime is 142440247. The reversal of 142440217 is 712044241.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110754576 + 31685641 = 10524^2 + 5629^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-142440217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 142440191 and 142440200.

It is not a weakly prime, because it can be changed into another prime (142440211) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71220108 + 71220109.

It is an arithmetic number, because the mean of its divisors is an integer number (71220109).

Almost surely, 2^142440217 is an apocalyptic number.

It is an amenable number.

142440217 is a deficient number, since it is larger than the sum of its proper divisors (1).

142440217 is an equidigital number, since it uses as much as digits as its factorization.

142440217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1792, while the sum is 25.

The square root of 142440217 is about 11934.8320893090. The cubic root of 142440217 is about 522.2489099803.

Adding to 142440217 its reverse (712044241), we get a palindrome (854484458).

The spelling of 142440217 in words is "one hundred forty-two million, four hundred forty thousand, two hundred seventeen".