721116742 has 4 divisors (see below), whose sum is σ = 1081675116. Its totient is φ = 360558370.

The previous prime is 721116731. The next prime is 721116743. The reversal of 721116742 is 247611127.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 247611127 = 4783 ⋅51769.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (721116743) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 180279184 + ... + 180279187.

It is an arithmetic number, because the mean of its divisors is an integer number (270418779).

Almost surely, 2^721116742 is an apocalyptic number.

721116742 is a deficient number, since it is larger than the sum of its proper divisors (360558374).

721116742 is a wasteful number, since it uses less digits than its factorization.

721116742 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 360558373.

The product of its digits is 4704, while the sum is 31.

The square root of 721116742 is about 26853.6169258445. The cubic root of 721116742 is about 896.7440963218.

Adding to 721116742 its reverse (247611127), we get a palindrome (968727869).

The spelling of 721116742 in words is "seven hundred twenty-one million, one hundred sixteen thousand, seven hundred forty-two".