121866646 has 16 divisors (see below), whose sum is σ = 209914560. Its totient is φ = 52478280.

The previous prime is 121866643. The next prime is 121866649. The reversal of 121866646 is 646668121.

121866646 = 89² + 90² + ... + 715².

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (121866643) and next prime (121866649).

It is a junction number, because it is equal to n+sod(n) for n = 121866599 and 121866608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121866643) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 145356 + ... + 146191.

It is an arithmetic number, because the mean of its divisors is an integer number (13119660).

Almost surely, 2^121866646 is an apocalyptic number.

121866646 is a deficient number, since it is larger than the sum of its proper divisors (88047914).

121866646 is a wasteful number, since it uses less digits than its factorization.

121866646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 291579.

The product of its digits is 82944, while the sum is 40.

The square root of 121866646 is about 11039.3227147321. The cubic root of 121866646 is about 495.7867921447.

The spelling of 121866646 in words is "one hundred twenty-one million, eight hundred sixty-six thousand, six hundred forty-six".