201387271681 has 2 divisors, whose sum is σ = 201387271682. Its totient is φ = 201387271680.

The previous prime is 201387271661. The next prime is 201387271699. The reversal of 201387271681 is 186172783102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 188807630400 + 12579641281 = 434520^2 + 112159^2 .

It is a cyclic number.

It is not a de Polignac number, because 201387271681 - 2¹⁷ = 201387140609 is a prime.

It is a super-2 number, since 2×201387271681² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (201387271661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100693635840 + 100693635841.

It is an arithmetic number, because the mean of its divisors is an integer number (100693635841).

Almost surely, 2^201387271681 is an apocalyptic number.

It is an amenable number.

201387271681 is a deficient number, since it is larger than the sum of its proper divisors (1).

201387271681 is an equidigital number, since it uses as much as digits as its factorization.

201387271681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 225792, while the sum is 46.

The spelling of 201387271681 in words is "two hundred one billion, three hundred eighty-seven million, two hundred seventy-one thousand, six hundred eighty-one".