121905216 has 224 divisors, whose sum is σ = 390144000. Its totient is φ = 37200384.

The previous prime is 121905167. The next prime is 121905233. The reversal of 121905216 is 612509121.

121905216 = T₈ + T₉ + ... + T₉₀₀.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 121905216.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1543065 + ... + 1543143.

Almost surely, 2^121905216 is an apocalyptic number.

121905216 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 121905216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (195072000).

121905216 is an abundant number, since it is smaller than the sum of its proper divisors (268238784).

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

121905216 is a wasteful number, since it uses less digits than its factorization.

121905216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166 (or 150 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 27.

The square root of 121905216 is about 11041.0695134122. The cubic root of 121905216 is about 495.8390910582.

The spelling of 121905216 in words is "one hundred twenty-one million, nine hundred five thousand, two hundred sixteen".