142540721 has 2 divisors, whose sum is σ = 142540722. Its totient is φ = 142540720.

The previous prime is 142540711. The next prime is 142540757. The reversal of 142540721 is 127045241.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 92640625 + 49900096 = 9625^2 + 7064^2 .

It is a cyclic number.

It is not a de Polignac number, because 142540721 - 2¹⁴ = 142524337 is a prime.

It is not a weakly prime, because it can be changed into another prime (142540711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71270360 + 71270361.

It is an arithmetic number, because the mean of its divisors is an integer number (71270361).

Almost surely, 2^142540721 is an apocalyptic number.

It is an amenable number.

142540721 is a deficient number, since it is larger than the sum of its proper divisors (1).

142540721 is an equidigital number, since it uses as much as digits as its factorization.

142540721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2240, while the sum is 26.

The square root of 142540721 is about 11939.0418794809. The cubic root of 142540721 is about 522.3717118252.

Adding to 142540721 its reverse (127045241), we get a palindrome (269585962).

The spelling of 142540721 in words is "one hundred forty-two million, five hundred forty thousand, seven hundred twenty-one".