521111121 has 16 divisors (see below), whose sum is σ = 719409600. Its totient is φ = 335131328.

The previous prime is 521111113. The next prime is 521111141. The reversal of 521111121 is 121111125.

It is a cyclic number.

It is not a de Polignac number, because 521111121 - 2³ = 521111113 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 521111121.

It is not an unprimeable number, because it can be changed into a prime (521111141) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 140590 + ... + 144248.

It is an arithmetic number, because the mean of its divisors is an integer number (44963100).

Almost surely, 2^521111121 is an apocalyptic number.

It is an amenable number.

521111121 is a deficient number, since it is larger than the sum of its proper divisors (198298479).

521111121 is a wasteful number, since it uses less digits than its factorization.

521111121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5328.

The product of its digits is 20, while the sum is 15.

The square root of 521111121 is about 22827.8584409489. The cubic root of 521111121 is about 804.7175023050.

Adding to 521111121 its reverse (121111125), we get a palindrome (642222246).

The spelling of 521111121 in words is "five hundred twenty-one million, one hundred eleven thousand, one hundred twenty-one".