121542541 has 4 divisors (see below), whose sum is σ = 122118784. Its totient is φ = 120966300.

The previous prime is 121542523. The next prime is 121542559. The reversal of 121542541 is 145245121.

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, and also an emirpimes, since its reverse is a distinct semiprime: 145245121 = 7 ⋅20749303.

It is an interprime number because it is at equal distance from previous prime (121542523) and next prime (121542559).

It is a de Polignac number, because none of the positive numbers 2^k-121542541 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 (121542581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 287805 + ... + 288226.

It is an arithmetic number, because the mean of its divisors is an integer number (30529696).

Almost surely, 2^121542541 is an apocalyptic number.

It is an amenable number.

121542541 is a deficient number, since it is larger than the sum of its proper divisors (576243).

121542541 is an equidigital number, since it uses as much as digits as its factorization.

121542541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 576242.

The product of its digits is 1600, while the sum is 25.

The square root of 121542541 is about 11024.6333725889. The cubic root of 121542541 is about 495.3468860569.

Adding to 121542541 its reverse (145245121), we get a palindrome (266787662).

The spelling of 121542541 in words is "one hundred twenty-one million, five hundred forty-two thousand, five hundred forty-one".