121191840 has 288 divisors, whose sum is σ = 516087936. Its totient is φ = 25159680.

The previous prime is 121191809. The next prime is 121191857. The reversal of 121191840 is 48191121.

It is a tau number, because it is divible by the number of its divisors (288).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 110334 + ... + 111426.

It is an arithmetic number, because the mean of its divisors is an integer number (1791972).

Almost surely, 2^121191840 is an apocalyptic number.

121191840 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 121191840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (258043968).

121191840 is an abundant number, since it is smaller than the sum of its proper divisors (394896096).

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

121191840 is a wasteful number, since it uses less digits than its factorization.

121191840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1132 (or 1121 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 27.

The square root of 121191840 is about 11008.7165464463. The cubic root of 121191840 is about 494.8699995314.

The spelling of 121191840 in words is "one hundred twenty-one million, one hundred ninety-one thousand, eight hundred forty".