121870 has 16 divisors (see below), whose sum is σ = 250848. Its totient is φ = 41760.

The previous prime is 121867. The next prime is 121883. The reversal of 121870 is 78121.

It is an Ulam number.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 801 + ... + 940.

It is an arithmetic number, because the mean of its divisors is an integer number (15678).

2¹²¹⁸⁷⁰ is an apocalyptic number.

121870 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121870 is an abundant number, since it is smaller than the sum of its proper divisors (128978).

It is a weird number, because it is abundant, but not a pseudoperfect number.

121870 is a wasteful number, since it uses less digits than its factorization.

121870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1755.

The product of its (nonzero) digits is 112, while the sum is 19.

The square root of 121870 is about 349.0988398720. The cubic root of 121870 is about 49.5791340432.

Adding to 121870 its reverse (78121), we get a palindrome (199991).

The spelling of 121870 in words is "one hundred twenty-one thousand, eight hundred seventy".