121951920 has 80 divisors (see below), whose sum is σ = 380913120. Its totient is φ = 32274432.

The previous prime is 121951883. The next prime is 121951933. The reversal of 121951920 is 29159121.

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (30).

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 15 ways as a sum of consecutive naturals, for example, 31026 + ... + 34734.

It is an arithmetic number, because the mean of its divisors is an integer number (4761414).

Almost surely, 2^121951920 is an apocalyptic number.

121951920 is a gapful number since it is divisible by the number (10) 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 121951920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (190456560).

121951920 is an abundant number, since it is smaller than the sum of its proper divisors (258961200).

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

121951920 is a wasteful number, since it uses less digits than its factorization.

121951920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3862 (or 3856 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 30.

The square root of 121951920 is about 11043.1843233734. The cubic root of 121951920 is about 495.9024044885.

The spelling of 121951920 in words is "one hundred twenty-one million, nine hundred fifty-one thousand, nine hundred twenty".