742721 has 4 divisors (see below), whose sum is σ = 848832. Its totient is φ = 636612.

The previous prime is 742717. The next prime is 742723. The reversal of 742721 is 127247.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 742721 - 2² = 742717 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (742723) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53045 + ... + 53058.

It is an arithmetic number, because the mean of its divisors is an integer number (212208).

2⁷⁴²⁷²¹ is an apocalyptic number.

It is an amenable number.

742721 is a deficient number, since it is larger than the sum of its proper divisors (106111).

742721 is a wasteful number, since it uses less digits than its factorization.

742721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106110.

The product of its digits is 784, while the sum is 23.

The square root of 742721 is about 861.8126246464. The cubic root of 742721 is about 90.5611442360.

Adding to 742721 its reverse (127247), we get a palindrome (869968).

The spelling of 742721 in words is "seven hundred forty-two thousand, seven hundred twenty-one", and thus it is an iban number.