121653 has 12 divisors (see below), whose sum is σ = 200928. Its totient is φ = 69480.

The previous prime is 121637. The next prime is 121661. The reversal of 121653 is 356121.

121653 is a `hidden beast` number, since 12 + 1 + 653 = 666.

It is not a de Polignac number, because 121653 - 2⁴ = 121637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 903 + ... + 1028.

It is an arithmetic number, because the mean of its divisors is an integer number (16744).

2¹²¹⁶⁵³ is an apocalyptic number.

It is an amenable number.

121653 is a deficient number, since it is larger than the sum of its proper divisors (79275).

121653 is a wasteful number, since it uses less digits than its factorization.

121653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1944 (or 1941 counting only the distinct ones).

The product of its digits is 180, while the sum is 18.

The square root of 121653 is about 348.7879011663. The cubic root of 121653 is about 49.5496899252.

Adding to 121653 its reverse (356121), we get a palindrome (477774).

The spelling of 121653 in words is "one hundred twenty-one thousand, six hundred fifty-three".