721540113 has 16 divisors (see below), whose sum is σ = 1099900800. Its totient is φ = 412154496.

The previous prime is 721540109. The next prime is 721540121. The reversal of 721540113 is 311045127.

It is not a de Polignac number, because 721540113 - 2² = 721540109 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (721540123) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 75213 + ... + 84261.

It is an arithmetic number, because the mean of its divisors is an integer number (68743800).

Almost surely, 2^721540113 is an apocalyptic number.

It is an amenable number.

721540113 is a deficient number, since it is larger than the sum of its proper divisors (378360687).

721540113 is a wasteful number, since it uses less digits than its factorization.

721540113 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12856.

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 721540113 is about 26861.4987109804. The cubic root of 721540113 is about 896.9195562012.

The spelling of 721540113 in words is "seven hundred twenty-one million, five hundred forty thousand, one hundred thirteen".