201387271661 has 2 divisors, whose sum is σ = 201387271662. Its totient is φ = 201387271660.

The previous prime is 201387271643. The next prime is 201387271681. The reversal of 201387271661 is 166172783102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 201337074436 + 50197225 = 448706^2 + 7085^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201387271661 is a prime.

It is a super-3 number, since 3×201387271661³ (a number of 35 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201387271681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100693635830 + 100693635831.

It is an arithmetic number, because the mean of its divisors is an integer number (100693635831).

Almost surely, 2^201387271661 is an apocalyptic number.

It is an amenable number.

201387271661 is a deficient number, since it is larger than the sum of its proper divisors (1).

201387271661 is an equidigital number, since it uses as much as digits as its factorization.

201387271661 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 169344, while the sum is 44.

The spelling of 201387271661 in words is "two hundred one billion, three hundred eighty-seven million, two hundred seventy-one thousand, six hundred sixty-one".