121686240 has 96 divisors (see below), whose sum is σ = 412818336. Its totient is φ = 29952000.

The previous prime is 121686223. The next prime is 121686247. The reversal of 121686240 is 42686121.

It is a tau number, because it is divible by the number of its divisors (96).

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

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

It is a junction number, because it is equal to n+sod(n) for n = 121686198 and 121686207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121686247) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3511 + ... + 15990.

It is an arithmetic number, because the mean of its divisors is an integer number (4300191).

Almost surely, 2^121686240 is an apocalyptic number.

121686240 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 121686240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (206409168).

121686240 is an abundant number, since it is smaller than the sum of its proper divisors (291132096).

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

121686240 is a wasteful number, since it uses less digits than its factorization.

121686240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19532 (or 19524 counting only the distinct ones).

The product of its (nonzero) digits is 4608, while the sum is 30.

The square root of 121686240 is about 11031.1486255965. The cubic root of 121686240 is about 495.5420243676.

The spelling of 121686240 in words is "one hundred twenty-one million, six hundred eighty-six thousand, two hundred forty".