142987321 has 2 divisors, whose sum is σ = 142987322. Its totient is φ = 142987320.

The previous prime is 142987291. The next prime is 142987333. The reversal of 142987321 is 123789241.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 130988025 + 11999296 = 11445^2 + 3464^2 .

It is an emirp because it is prime and its reverse (123789241) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 142987321 - 2¹⁷ = 142856249 is a prime.

It is not a weakly prime, because it can be changed into another prime (142987921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71493660 + 71493661.

It is an arithmetic number, because the mean of its divisors is an integer number (71493661).

Almost surely, 2^142987321 is an apocalyptic number.

It is an amenable number.

142987321 is a deficient number, since it is larger than the sum of its proper divisors (1).

142987321 is an equidigital number, since it uses as much as digits as its factorization.

142987321 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24192, while the sum is 37.

The square root of 142987321 is about 11957.7305957276. The cubic root of 142987321 is about 522.9166975748.

The spelling of 142987321 in words is "one hundred forty-two million, nine hundred eighty-seven thousand, three hundred twenty-one".