142440421 has 2 divisors, whose sum is σ = 142440422. Its totient is φ = 142440420.

The previous prime is 142440349. The next prime is 142440427. The reversal of 142440421 is 124044241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 141943396 + 497025 = 11914^2 + 705^2 .

It is an emirp because it is prime and its reverse (124044241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 142440421 - 2⁷ = 142440293 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 142440392 and 142440401.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (142440427) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71220210 + 71220211.

It is an arithmetic number, because the mean of its divisors is an integer number (71220211).

Almost surely, 2^142440421 is an apocalyptic number.

It is an amenable number.

142440421 is a deficient number, since it is larger than the sum of its proper divisors (1).

142440421 is an equidigital number, since it uses as much as digits as its factorization.

142440421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1024, while the sum is 22.

The square root of 142440421 is about 11934.8406357186. The cubic root of 142440421 is about 522.2491592983.

Adding to 142440421 its reverse (124044241), we get a palindrome (266484662).

The spelling of 142440421 in words is "one hundred forty-two million, four hundred forty thousand, four hundred twenty-one".