121543541 has 4 divisors (see below), whose sum is σ = 138906912. Its totient is φ = 104180172.

The previous prime is 121543517. The next prime is 121543573. The reversal of 121543541 is 145345121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121543541 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121543541.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121543511) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8681675 + ... + 8681688.

It is an arithmetic number, because the mean of its divisors is an integer number (34726728).

Almost surely, 2^121543541 is an apocalyptic number.

It is an amenable number.

121543541 is a deficient number, since it is larger than the sum of its proper divisors (17363371).

121543541 is an equidigital number, since it uses as much as digits as its factorization.

121543541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17363370.

The product of its digits is 2400, while the sum is 26.

The square root of 121543541 is about 11024.6787254777. The cubic root of 121543541 is about 495.3482445539.

Adding to 121543541 its reverse (145345121), we get a palindrome (266888662).

The spelling of 121543541 in words is "one hundred twenty-one million, five hundred forty-three thousand, five hundred forty-one".