120521981 has 2 divisors, whose sum is σ = 120521982.
Its totient is φ = 120521980.
The previous prime is 120521977. The next prime is 120522011. The reversal of 120521981 is 189125021.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 115369081 + 5152900 = 10741^2 + 2270^2
It is a cyclic number.
It is not a de Polignac number, because 120521981 - 22 = 120521977 is a prime.
It is a super-2 number, since 2×1205219812 = 29051095808328722, which contains 22 as substring.
It is a Sophie Germain prime.
It is a Chen prime.
It is a Curzon number.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (120521971) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60260990 + 60260991.
It is an arithmetic number, because the mean of its divisors is an integer number (60260991).
Almost surely, 2120521981 is an apocalyptic number.
It is an amenable number.
120521981 is a deficient number, since it is larger than the sum of its proper divisors (1).
120521981 is an equidigital number, since it uses as much as digits as its factorization.
120521981 is an evil number, because the sum of its binary digits is even.
The product of its (nonzero) digits is 1440, while the sum is 29.
The square root of 120521981 is about 10978.2503615103.
The cubic root of 120521981 is about 493.9565558674.
The spelling of 120521981 in words is "one hundred twenty million, five hundred twenty-one thousand, nine hundred eighty-one".