201981289 has 2 divisors, whose sum is σ = 201981290. Its totient is φ = 201981288.

The previous prime is 201981281. The next prime is 201981313. The reversal of 201981289 is 982189102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 174240000 + 27741289 = 13200^2 + 5267^2 .

It is a cyclic number.

It is not a de Polignac number, because 201981289 - 2³ = 201981281 is a prime.

It is a super-2 number, since 2×201981289² = 81592882212203042, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (201981281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100990644 + 100990645.

It is an arithmetic number, because the mean of its divisors is an integer number (100990645).

Almost surely, 2^201981289 is an apocalyptic number.

It is an amenable number.

201981289 is a deficient number, since it is larger than the sum of its proper divisors (1).

201981289 is an equidigital number, since it uses as much as digits as its factorization.

201981289 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20736, while the sum is 40.

The square root of 201981289 is about 14212.0121376250. The cubic root of 201981289 is about 586.7283137626.

The spelling of 201981289 in words is "two hundred one million, nine hundred eighty-one thousand, two hundred eighty-nine".