121669 has 6 divisors (see below), whose sum is σ = 129554. Its totient is φ = 114240.

The previous prime is 121661. The next prime is 121687. The reversal of 121669 is 966121.

It can be written as a sum of positive squares in 3 ways, for example, as 12769 + 108900 = 113^2 + 330^2 .

It is not a de Polignac number, because 121669 - 2³ = 121661 is a prime.

It is a super-2 number, since 2×121669² = 29606691122, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121661) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 79 + ... + 499.

2¹²¹⁶⁶⁹ is an apocalyptic number.

It is an amenable number.

121669 is a deficient number, since it is larger than the sum of its proper divisors (7885).

121669 is an equidigital number, since it uses as much as digits as its factorization.

121669 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 455 (or 438 counting only the distinct ones).

The product of its digits is 648, while the sum is 25.

The square root of 121669 is about 348.8108369876. The cubic root of 121669 is about 49.5518621152.

It can be divided in two parts, 12 and 1669, that added together give a square (1681 = 41²).

The spelling of 121669 in words is "one hundred twenty-one thousand, six hundred sixty-nine".