121989151 has 8 divisors (see below), whose sum is σ = 125072640. Its totient is φ = 118916952.

The previous prime is 121989149. The next prime is 121989163. The reversal of 121989151 is 151989121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121989151 - 2¹ = 121989149 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121989151.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121989121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21690 + ... + 26728.

It is an arithmetic number, because the mean of its divisors is an integer number (15634080).

Almost surely, 2^121989151 is an apocalyptic number.

121989151 is a deficient number, since it is larger than the sum of its proper divisors (3083489).

121989151 is an equidigital number, since it uses as much as digits as its factorization.

121989151 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5645.

The product of its digits is 6480, while the sum is 37.

The square root of 121989151 is about 11044.8698951142. The cubic root of 121989151 is about 495.9528644399.

The spelling of 121989151 in words is "one hundred twenty-one million, nine hundred eighty-nine thousand, one hundred fifty-one".