142721 has 6 divisors (see below), whose sum is σ = 148722. Its totient is φ = 136880.

The previous prime is 142711. The next prime is 142733. The reversal of 142721 is 127241.

It can be written as a sum of positive squares in only one way, i.e., 87025 + 55696 = 295^2 + 236^2 .

It is not a de Polignac number, because 142721 - 2⁶ = 142657 is a prime.

It is a Duffinian number.

It is a plaindrome in base 9.

It is a self number, because there is not a number n which added to its sum of digits gives 142721.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (142711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2390 + ... + 2448.

It is an arithmetic number, because the mean of its divisors is an integer number (24787).

2¹⁴²⁷²¹ is an apocalyptic number.

It is an amenable number.

142721 is a deficient number, since it is larger than the sum of its proper divisors (6001).

142721 is an frugal number, since it uses more digits than its factorization.

142721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 159 (or 100 counting only the distinct ones).

The product of its digits is 112, while the sum is 17.

The square root of 142721 is about 377.7843300085. The cubic root of 142721 is about 52.2591843016.

Adding to 142721 its reverse (127241), we get a palindrome (269962).

The spelling of 142721 in words is "one hundred forty-two thousand, seven hundred twenty-one", and thus it is an iban number.