205541099997631 has 2 divisors, whose sum is σ = 205541099997632. Its totient is φ = 205541099997630.

The previous prime is 205541099997581. The next prime is 205541099997707. The reversal of 205541099997631 is 136799990145502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-205541099997631 is a prime.

It is a super-2 number, since 2×205541099997631² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (205541099997031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 102770549998815 + 102770549998816.

It is an arithmetic number, because the mean of its divisors is an integer number (102770549998816).

Almost surely, 2^{205541099997631} is an apocalyptic number.

205541099997631 is a deficient number, since it is larger than the sum of its proper divisors (1).

205541099997631 is an equidigital number, since it uses as much as digits as its factorization.

205541099997631 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 165337200, while the sum is 70.

The spelling of 205541099997631 in words is "two hundred five trillion, five hundred forty-one billion, ninety-nine million, nine hundred ninety-seven thousand, six hundred thirty-one".