121905656 has 16 divisors (see below), whose sum is σ = 229201440. Its totient is φ = 60785280.

The previous prime is 121905613. The next prime is 121905659. The reversal of 121905656 is 656509121.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121905659) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17825 + ... + 23696.

It is an arithmetic number, because the mean of its divisors is an integer number (14325090).

Almost surely, 2^121905656 is an apocalyptic number.

It is an amenable number.

121905656 is a deficient number, since it is larger than the sum of its proper divisors (107295784).

121905656 is a wasteful number, since it uses less digits than its factorization.

121905656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41894 (or 41890 counting only the distinct ones).

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 121905656 is about 11041.0894390001. The cubic root of 121905656 is about 495.8396876117.

The spelling of 121905656 in words is "one hundred twenty-one million, nine hundred five thousand, six hundred fifty-six".