121665353 has 4 divisors (see below), whose sum is σ = 125860740. Its totient is φ = 117469968.

The previous prime is 121665347. The next prime is 121665371. The reversal of 121665353 is 353566121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 353566121 = 3769 ⋅93809.

It can be written as a sum of positive squares in 2 ways, for example, as 43731769 + 77933584 = 6613^2 + 8828^2 .

It is a cyclic number.

It is not a de Polignac number, because 121665353 - 2⁴ = 121665337 is a prime.

It is a super-2 number, since 2×121665353² = 29604916241229218, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121665053) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2097650 + ... + 2097707.

It is an arithmetic number, because the mean of its divisors is an integer number (31465185).

Almost surely, 2^121665353 is an apocalyptic number.

It is an amenable number.

121665353 is a deficient number, since it is larger than the sum of its proper divisors (4195387).

121665353 is an equidigital number, since it uses as much as digits as its factorization.

121665353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4195386.

The product of its digits is 16200, while the sum is 32.

The square root of 121665353 is about 11030.2018567205. The cubic root of 121665353 is about 495.5136700839.

The spelling of 121665353 in words is "one hundred twenty-one million, six hundred sixty-five thousand, three hundred fifty-three".