2005194608621 has 2 divisors, whose sum is σ = 2005194608622. Its totient is φ = 2005194608620.

The previous prime is 2005194608611. The next prime is 2005194608699. The reversal of 2005194608621 is 1268064915002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1414470169225 + 590724439396 = 1189315^2 + 768586^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2005194608621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2005194608611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1002597304310 + 1002597304311.

It is an arithmetic number, because the mean of its divisors is an integer number (1002597304311).

Almost surely, 2^{2005194608621} is an apocalyptic number.

It is an amenable number.

2005194608621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2005194608621 is an equidigital number, since it uses as much as digits as its factorization.

2005194608621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 207360, while the sum is 44.

The spelling of 2005194608621 in words is "two trillion, five billion, one hundred ninety-four million, six hundred eight thousand, six hundred twenty-one".