2120201209981 has 2 divisors, whose sum is σ = 2120201209982. Its totient is φ = 2120201209980.

The previous prime is 2120201209957. The next prime is 2120201210027. The reversal of 2120201209981 is 1899021020212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1979100308025 + 141100901956 = 1406805^2 + 375634^2 .

It is a cyclic number.

It is not a de Polignac number, because 2120201209981 - 2⁵ = 2120201209949 is a prime.

It is a super-2 number, since 2×2120201209981² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 2120201209981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2120201209781) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060100604990 + 1060100604991.

It is an arithmetic number, because the mean of its divisors is an integer number (1060100604991).

Almost surely, 2^{2120201209981} is an apocalyptic number.

It is an amenable number.

2120201209981 is a deficient number, since it is larger than the sum of its proper divisors (1).

2120201209981 is an equidigital number, since it uses as much as digits as its factorization.

2120201209981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10368, while the sum is 37.

The spelling of 2120201209981 in words is "two trillion, one hundred twenty billion, two hundred one million, two hundred nine thousand, nine hundred eighty-one".