121005541 has 4 divisors (see below), whose sum is σ = 128123532. Its totient is φ = 113887552.

The previous prime is 121005539. The next prime is 121005581. The reversal of 121005541 is 145500121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 145500121 = 13 ⋅11192317.

It can be written as a sum of positive squares in 2 ways, for example, as 81993025 + 39012516 = 9055^2 + 6246^2 .

It is a cyclic number.

It is not a de Polignac number, because 121005541 - 2¹ = 121005539 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 (121005581) 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, 3558970 + ... + 3559003.

It is an arithmetic number, because the mean of its divisors is an integer number (32030883).

Almost surely, 2^121005541 is an apocalyptic number.

It is an amenable number.

121005541 is a deficient number, since it is larger than the sum of its proper divisors (7117991).

121005541 is an equidigital number, since it uses as much as digits as its factorization.

121005541 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7117990.

The product of its (nonzero) digits is 200, while the sum is 19.

The square root of 121005541 is about 11000.2518607530. The cubic root of 121005541 is about 494.6162941464.

Adding to 121005541 its reverse (145500121), we get a palindrome (266505662).

The spelling of 121005541 in words is "one hundred twenty-one million, five thousand, five hundred forty-one".