6557121 has 18 divisors (see below), whose sum is σ = 10065302. Its totient is φ = 4112640.

The previous prime is 6557101. The next prime is 6557123. The reversal of 6557121 is 1217556.

6557121 is a `hidden beast` number, since 655 + 7 + 1 + 2 + 1 = 666.

It can be written as a sum of positive squares in 3 ways, for example, as 608400 + 5948721 = 780^2 + 2439^2 .

It is not a de Polignac number, because 6557121 - 2⁷ = 6556993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6557123) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 1341 + ... + 3861.

Almost surely, 2^6557121 is an apocalyptic number.

It is an amenable number.

6557121 is a deficient number, since it is larger than the sum of its proper divisors (3508181).

6557121 is a wasteful number, since it uses less digits than its factorization.

6557121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2561 (or 2541 counting only the distinct ones).

The product of its digits is 2100, while the sum is 27.

The square root of 6557121 is about 2560.6876029692. The cubic root of 6557121 is about 187.1706431337.

It can be divided in two parts, 6557 and 121, that multiplied together give a palindrome (793397).

The spelling of 6557121 in words is "six million, five hundred fifty-seven thousand, one hundred twenty-one".