121403656 has 48 divisors (see below), whose sum is σ = 252040320. Its totient is φ = 54780000.

The previous prime is 121403629. The next prime is 121403677. The reversal of 121403656 is 656304121.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 161281 + ... + 162031.

It is an arithmetic number, because the mean of its divisors is an integer number (5250840).

Almost surely, 2^121403656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121403656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126020160).

121403656 is an abundant number, since it is smaller than the sum of its proper divisors (130636664).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121403656 is a wasteful number, since it uses less digits than its factorization.

121403656 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 946 (or 931 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 121403656 is about 11018.3327232390. The cubic root of 121403656 is about 495.1581387741.

Adding to 121403656 its reverse (656304121), we get a palindrome (777707777).

The spelling of 121403656 in words is "one hundred twenty-one million, four hundred three thousand, six hundred fifty-six".