2118705521 has 2 divisors, whose sum is σ = 2118705522. Its totient is φ = 2118705520.

The previous prime is 2118705487. The next prime is 2118705541. The reversal of 2118705521 is 1255078112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2070250000 + 48455521 = 45500^2 + 6961^2 .

It is a cyclic number.

It is not a de Polignac number, because 2118705521 - 2¹⁸ = 2118443377 is a prime.

It is not a weakly prime, because it can be changed into another prime (2118705541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1059352760 + 1059352761.

It is an arithmetic number, because the mean of its divisors is an integer number (1059352761).

Almost surely, 2^2118705521 is an apocalyptic number.

It is an amenable number.

2118705521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2118705521 is an equidigital number, since it uses as much as digits as its factorization.

2118705521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5600, while the sum is 32.

The square root of 2118705521 is about 46029.3984427344. The cubic root of 2118705521 is about 1284.3701376996.

The spelling of 2118705521 in words is "two billion, one hundred eighteen million, seven hundred five thousand, five hundred twenty-one".