121643541 has 6 divisors (see below), whose sum is σ = 175707350. Its totient is φ = 81095688.

The previous prime is 121643539. The next prime is 121643569. The reversal of 121643541 is 145346121.

It is a happy number.

121643541 is a `hidden beast` number, since 12 + 1 + 643 + 5 + 4 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 81270225 + 40373316 = 9015^2 + 6354^2 .

It is not a de Polignac number, because 121643541 - 2¹ = 121643539 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121643341) 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, 6757966 + ... + 6757983.

Almost surely, 2^121643541 is an apocalyptic number.

It is an amenable number.

121643541 is a deficient number, since it is larger than the sum of its proper divisors (54063809).

121643541 is a wasteful number, since it uses less digits than its factorization.

121643541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13515955 (or 13515952 counting only the distinct ones).

The product of its digits is 2880, while the sum is 27.

The square root of 121643541 is about 11029.2130725632. The cubic root of 121643541 is about 495.4840566405.

Adding to 121643541 its reverse (145346121), we get a palindrome (266989662).

The spelling of 121643541 in words is "one hundred twenty-one million, six hundred forty-three thousand, five hundred forty-one".