121765543 has 4 divisors (see below), whose sum is σ = 128928240. Its totient is φ = 114602848.

The previous prime is 121765541. The next prime is 121765559. The reversal of 121765543 is 345567121.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 121765543 - 2¹ = 121765541 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121765499 and 121765508.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121765541) 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, 3581323 + ... + 3581356.

It is an arithmetic number, because the mean of its divisors is an integer number (32232060).

Almost surely, 2^121765543 is an apocalyptic number.

121765543 is a deficient number, since it is larger than the sum of its proper divisors (7162697).

121765543 is an equidigital number, since it uses as much as digits as its factorization.

121765543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7162696.

The product of its digits is 25200, while the sum is 34.

The square root of 121765543 is about 11034.7425434398. The cubic root of 121765543 is about 495.6496493420.

The spelling of 121765543 in words is "one hundred twenty-one million, seven hundred sixty-five thousand, five hundred forty-three".