10120721 has 16 divisors (see below), whose sum is σ = 11433744. Its totient is φ = 8895744.

The previous prime is 10120709. The next prime is 10120723. The reversal of 10120721 is 12702101.

It can be written as a sum of positive squares in 8 ways, for example, as 541696 + 9579025 = 736^2 + 3095^2 .

It is not a de Polignac number, because 10120721 - 2⁶ = 10120657 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10120696 and 10120705.

It is not an unprimeable number, because it can be changed into a prime (10120723) 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, 25295 + ... + 25691.

It is an arithmetic number, because the mean of its divisors is an integer number (714609).

Almost surely, 2^10120721 is an apocalyptic number.

It is an amenable number.

10120721 is a deficient number, since it is larger than the sum of its proper divisors (1313023).

10120721 is a wasteful number, since it uses less digits than its factorization.

10120721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 500.

The product of its (nonzero) digits is 28, while the sum is 14.

The square root of 10120721 is about 3181.3080643031. The cubic root of 10120721 is about 216.3069552721.

Adding to 10120721 its reverse (12702101), we get a palindrome (22822822).

The spelling of 10120721 in words is "ten million, one hundred twenty thousand, seven hundred twenty-one".