120521578781 has 2 divisors, whose sum is σ = 120521578782. Its totient is φ = 120521578780.

The previous prime is 120521578777. The next prime is 120521578799. The reversal of 120521578781 is 187875125021.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120085813156 + 435765625 = 346534^2 + 20875^2 .

It is a cyclic number.

It is not a de Polignac number, because 120521578781 - 2² = 120521578777 is a prime.

It is a super-2 number, since 2×120521578781² (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 (120521508781) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60260789390 + 60260789391.

It is an arithmetic number, because the mean of its divisors is an integer number (60260789391).

Almost surely, 2^120521578781 is an apocalyptic number.

It is an amenable number.

120521578781 is a deficient number, since it is larger than the sum of its proper divisors (1).

120521578781 is an equidigital number, since it uses as much as digits as its factorization.

120521578781 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 313600, while the sum is 47.

The spelling of 120521578781 in words is "one hundred twenty billion, five hundred twenty-one million, five hundred seventy-eight thousand, seven hundred eighty-one".