6535872121 has 2 divisors, whose sum is σ = 6535872122. Its totient is φ = 6535872120.

The previous prime is 6535872097. The next prime is 6535872143. The reversal of 6535872121 is 1212785356.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5846284521 + 689587600 = 76461^2 + 26260^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6535872121 is a prime.

It is not a weakly prime, because it can be changed into another prime (6535872151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3267936060 + 3267936061.

It is an arithmetic number, because the mean of its divisors is an integer number (3267936061).

Almost surely, 2^6535872121 is an apocalyptic number.

It is an amenable number.

6535872121 is a deficient number, since it is larger than the sum of its proper divisors (1).

6535872121 is an equidigital number, since it uses as much as digits as its factorization.

6535872121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 100800, while the sum is 40.

The square root of 6535872121 is about 80844.7408369895. The cubic root of 6535872121 is about 1869.6824382824.

The spelling of 6535872121 in words is "six billion, five hundred thirty-five million, eight hundred seventy-two thousand, one hundred twenty-one".