142520821 has 2 divisors, whose sum is σ = 142520822. Its totient is φ = 142520820.

The previous prime is 142520801. The next prime is 142520831. The reversal of 142520821 is 128025241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95062500 + 47458321 = 9750^2 + 6889^2 .

It is an emirp because it is prime and its reverse (128025241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 142520821 - 2⁵ = 142520789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (142520801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71260410 + 71260411.

It is an arithmetic number, because the mean of its divisors is an integer number (71260411).

Almost surely, 2^142520821 is an apocalyptic number.

It is an amenable number.

142520821 is a deficient number, since it is larger than the sum of its proper divisors (1).

142520821 is an equidigital number, since it uses as much as digits as its factorization.

142520821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1280, while the sum is 25.

The square root of 142520821 is about 11938.2084501821. The cubic root of 142520821 is about 522.3474013900.

It can be divided in two parts, 142520 and 821, that added together give a palindrome (143341).

The spelling of 142520821 in words is "one hundred forty-two million, five hundred twenty thousand, eight hundred twenty-one".