121809664 has 36 divisors (see below), whose sum is σ = 251003200. Its totient is φ = 58936320.

The previous prime is 121809643. The next prime is 121809673. The reversal of 121809664 is 466908121.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 262 + ... + 15610.

Almost surely, 2^121809664 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 121809664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (125501600).

121809664 is an abundant number, since it is smaller than the sum of its proper divisors (129193536).

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

121809664 is an equidigital number, since it uses as much as digits as its factorization.

121809664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15396 (or 15382 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 121809664 is about 11036.7415481201. The cubic root of 121809664 is about 495.7095073195.

The spelling of 121809664 in words is "one hundred twenty-one million, eight hundred nine thousand, six hundred sixty-four".