143499721 has 2 divisors, whose sum is σ = 143499722. Its totient is φ = 143499720.

The previous prime is 143499683. The next prime is 143499731. The reversal of 143499721 is 127994341.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 139499721 + 4000000 = 11811^2 + 2000^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-143499721 is a prime.

It is not a weakly prime, because it can be changed into another prime (143499731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 71749860 + 71749861.

It is an arithmetic number, because the mean of its divisors is an integer number (71749861).

Almost surely, 2^143499721 is an apocalyptic number.

It is an amenable number.

143499721 is a deficient number, since it is larger than the sum of its proper divisors (1).

143499721 is an equidigital number, since it uses as much as digits as its factorization.

143499721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 54432, while the sum is 40.

The square root of 143499721 is about 11979.1369054703. The cubic root of 143499721 is about 523.5405829404.

The spelling of 143499721 in words is "one hundred forty-three million, four hundred ninety-nine thousand, seven hundred twenty-one".