121890169 has 2 divisors, whose sum is σ = 121890170. Its totient is φ = 121890168.

The previous prime is 121890151. The next prime is 121890191. The reversal of 121890169 is 961098121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 120231225 + 1658944 = 10965^2 + 1288^2 .

It is a cyclic number.

It is not a de Polignac number, because 121890169 - 2⁵ = 121890137 is a prime.

It is a super-2 number, since 2×121890169² = 29714426597697122, which contains 22 as substring.

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

It is not a weakly prime, because it can be changed into another prime (121890199) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60945084 + 60945085.

It is an arithmetic number, because the mean of its divisors is an integer number (60945085).

Almost surely, 2^121890169 is an apocalyptic number.

It is an amenable number.

121890169 is a deficient number, since it is larger than the sum of its proper divisors (1).

121890169 is an equidigital number, since it uses as much as digits as its factorization.

121890169 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7776, while the sum is 37.

The square root of 121890169 is about 11040.3880819471. The cubic root of 121890169 is about 495.8186894215.

The spelling of 121890169 in words is "one hundred twenty-one million, eight hundred ninety thousand, one hundred sixty-nine".