201078449981 has 2 divisors, whose sum is σ = 201078449982. Its totient is φ = 201078449980.

The previous prime is 201078449953. The next prime is 201078449993. The reversal of 201078449981 is 189944870102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 200945992900 + 132457081 = 448270^2 + 11509^2 .

It is a cyclic number.

It is not a de Polignac number, because 201078449981 - 2²² = 201074255677 is a prime.

It is a super-2 number, since 2×201078449981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (201078449911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100539224990 + 100539224991.

It is an arithmetic number, because the mean of its divisors is an integer number (100539224991).

Almost surely, 2^201078449981 is an apocalyptic number.

It is an amenable number.

201078449981 is a deficient number, since it is larger than the sum of its proper divisors (1).

201078449981 is an equidigital number, since it uses as much as digits as its factorization.

201078449981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1161216, while the sum is 53.

The spelling of 201078449981 in words is "two hundred one billion, seventy-eight million, four hundred forty-nine thousand, nine hundred eighty-one".