210120029981 has 2 divisors, whose sum is σ = 210120029982. Its totient is φ = 210120029980.

The previous prime is 210120029947. The next prime is 210120030023. The reversal of 210120029981 is 189920021012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 201727637881 + 8392392100 = 449141^2 + 91610^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-210120029981 is a prime.

It is a super-2 number, since 2×210120029981² (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 (210120029941) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105060014990 + 105060014991.

It is an arithmetic number, because the mean of its divisors is an integer number (105060014991).

Almost surely, 2^210120029981 is an apocalyptic number.

It is an amenable number.

210120029981 is a deficient number, since it is larger than the sum of its proper divisors (1).

210120029981 is an equidigital number, since it uses as much as digits as its factorization.

210120029981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 35.

The spelling of 210120029981 in words is "two hundred ten billion, one hundred twenty million, twenty-nine thousand, nine hundred eighty-one".