2506121557 has 2 divisors, whose sum is σ = 2506121558. Its totient is φ = 2506121556.

The previous prime is 2506121549. The next prime is 2506121567. The reversal of 2506121557 is 7551216052.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1887554916 + 618566641 = 43446^2 + 24871^2 .

It is a cyclic number.

It is not a de Polignac number, because 2506121557 - 2³ = 2506121549 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2506121567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1253060778 + 1253060779.

It is an arithmetic number, because the mean of its divisors is an integer number (1253060779).

Almost surely, 2^2506121557 is an apocalyptic number.

It is an amenable number.

2506121557 is a deficient number, since it is larger than the sum of its proper divisors (1).

2506121557 is an equidigital number, since it uses as much as digits as its factorization.

2506121557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 21000, while the sum is 34.

The square root of 2506121557 is about 50061.1781423490. The cubic root of 2506121557 is about 1358.3156695040.

The spelling of 2506121557 in words is "two billion, five hundred six million, one hundred twenty-one thousand, five hundred fifty-seven".