121661120 has 84 divisors (see below), whose sum is σ = 337047840. Its totient is φ = 41707008.

The previous prime is 121661117. The next prime is 121661167. The reversal of 121661120 is 21166121.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 121661092 and 121661101.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11801 + ... + 19559.

Almost surely, 2^121661120 is an apocalyptic number.

121661120 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 121661120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (168523920).

121661120 is an abundant number, since it is smaller than the sum of its proper divisors (215386720).

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

121661120 is an equidigital number, since it uses as much as digits as its factorization.

121661120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7790 (or 7773 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 20.

The square root of 121661120 is about 11030.0099727969. The cubic root of 121661120 is about 495.5079233542.

The spelling of 121661120 in words is "one hundred twenty-one million, six hundred sixty-one thousand, one hundred twenty".