121989127 has 16 divisors (see below), whose sum is σ = 139491072. Its totient is φ = 105684480.

The previous prime is 121989121. The next prime is 121989143. The reversal of 121989127 is 721989121.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121989127 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 121989127.

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 15 ways as a sum of consecutive naturals, for example, 122602 + ... + 123592.

It is an arithmetic number, because the mean of its divisors is an integer number (8718192).

Almost surely, 2^121989127 is an apocalyptic number.

121989127 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

121989127 is a deficient number, since it is larger than the sum of its proper divisors (17501945).

121989127 is a wasteful number, since it uses less digits than its factorization.

121989127 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1578.

The product of its digits is 18144, while the sum is 40.

The square root of 121989127 is about 11044.8688086369. The cubic root of 121989127 is about 495.9528319155.

The spelling of 121989127 in words is "one hundred twenty-one million, nine hundred eighty-nine thousand, one hundred twenty-seven".