721431442 has 16 divisors (see below), whose sum is σ = 1138136832. Its totient is φ = 342491760.

The previous prime is 721431377. The next prime is 721431493. The reversal of 721431442 is 244134127.

It is a self number, because there is not a number n which added to its sum of digits gives 721431442.

It is an unprimeable number.

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 in 7 ways as a sum of consecutive naturals, for example, 106488 + ... + 113059.

It is an arithmetic number, because the mean of its divisors is an integer number (71133552).

Almost surely, 2^721431442 is an apocalyptic number.

721431442 is a deficient number, since it is larger than the sum of its proper divisors (416705390).

721431442 is a wasteful number, since it uses less digits than its factorization.

721431442 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 219633.

The product of its digits is 5376, while the sum is 28.

The square root of 721431442 is about 26859.4758325623. The cubic root of 721431442 is about 896.8745256538.

Adding to 721431442 its reverse (244134127), we get a palindrome (965565569).

The spelling of 721431442 in words is "seven hundred twenty-one million, four hundred thirty-one thousand, four hundred forty-two".