726121 has 12 divisors (see below), whose sum is σ = 847476. Its totient is φ = 619520.

The previous prime is 726109. The next prime is 726137. The reversal of 726121 is 121627.

It can be written as a sum of positive squares in 2 ways, for example, as 435600 + 290521 = 660^2 + 539^2 .

It is not a de Polignac number, because 726121 - 2⁷ = 725993 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (726101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1881 + ... + 2233.

It is an arithmetic number, because the mean of its divisors is an integer number (70623).

2⁷²⁶¹²¹ is an apocalyptic number.

It is an amenable number.

726121 is a deficient number, since it is larger than the sum of its proper divisors (121355).

726121 is a wasteful number, since it uses less digits than its factorization.

726121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392 (or 381 counting only the distinct ones).

The product of its digits is 168, while the sum is 19.

The square root of 726121 is about 852.1273379020. The cubic root of 726121 is about 89.8813663252.

Adding to 726121 its reverse (121627), we get a palindrome (847748).

The spelling of 726121 in words is "seven hundred twenty-six thousand, one hundred twenty-one".