121972506577 has 4 divisors (see below), whose sum is σ = 121974052660. Its totient is φ = 121970960496.

The previous prime is 121972506527. The next prime is 121972506611. The reversal of 121972506577 is 775605279121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 50674962321 + 71297544256 = 225111^2 + 267016^2 .

It is a cyclic number.

It is not a de Polignac number, because 121972506577 - 2⁷ = 121972506449 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121972506527) 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 in 3 ways as a sum of consecutive naturals, for example, 647958 + ... + 814735.

It is an arithmetic number, because the mean of its divisors is an integer number (30493513165).

Almost surely, 2^121972506577 is an apocalyptic number.

It is an amenable number.

121972506577 is a deficient number, since it is larger than the sum of its proper divisors (1546083).

121972506577 is an equidigital number, since it uses as much as digits as its factorization.

121972506577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1546082.

The product of its (nonzero) digits is 1852200, while the sum is 52.

The spelling of 121972506577 in words is "one hundred twenty-one billion, nine hundred seventy-two million, five hundred six thousand, five hundred seventy-seven".