121650555506 has 4 divisors (see below), whose sum is σ = 182475833262. Its totient is φ = 60825277752.

The previous prime is 121650555503. The next prime is 121650555581. The reversal of 121650555506 is 605555056121.

It is a happy number.

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

It can be written as a sum of positive squares in only one way, i.e., 119982568225 + 1667987281 = 346385^2 + 40841^2 .

It is not an unprimeable number, because it can be changed into a prime (121650555503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30412638875 + ... + 30412638878.

Almost surely, 2^121650555506 is an apocalyptic number.

121650555506 is a deficient number, since it is larger than the sum of its proper divisors (60825277756).

121650555506 is an equidigital number, since it uses as much as digits as its factorization.

121650555506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60825277755.

The product of its (nonzero) digits is 225000, while the sum is 41.

The spelling of 121650555506 in words is "one hundred twenty-one billion, six hundred fifty million, five hundred fifty-five thousand, five hundred six".