2521136221 has 2 divisors, whose sum is σ = 2521136222. Its totient is φ = 2521136220.

The previous prime is 2521136213. The next prime is 2521136263. The reversal of 2521136221 is 1226311252.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1512120996 + 1009015225 = 38886^2 + 31765^2 .

It is a cyclic number.

It is not a de Polignac number, because 2521136221 - 2³ = 2521136213 is a prime.

It is a super-2 number, since 2×2521136221² = 12712255689676321682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2521137221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1260568110 + 1260568111.

It is an arithmetic number, because the mean of its divisors is an integer number (1260568111).

Almost surely, 2^2521136221 is an apocalyptic number.

It is an amenable number.

2521136221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2521136221 is an equidigital number, since it uses as much as digits as its factorization.

2521136221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

The square root of 2521136221 is about 50210.9173487201. The cubic root of 2521136221 is about 1361.0229150088.

Adding to 2521136221 its reverse (1226311252), we get a palindrome (3747447473).

The spelling of 2521136221 in words is "two billion, five hundred twenty-one million, one hundred thirty-six thousand, two hundred twenty-one".