121543985 has 4 divisors (see below), whose sum is σ = 145852788. Its totient is φ = 97235184.

The previous prime is 121543979. The next prime is 121543987. The reversal of 121543985 is 589345121.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 38241856 + 83302129 = 6184^2 + 9127^2 .

It is a cyclic number.

It is not a de Polignac number, because 121543985 - 2⁶ = 121543921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121543987) 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, 12154394 + ... + 12154403.

It is an arithmetic number, because the mean of its divisors is an integer number (36463197).

Almost surely, 2^121543985 is an apocalyptic number.

It is an amenable number.

121543985 is a deficient number, since it is larger than the sum of its proper divisors (24308803).

121543985 is an equidigital number, since it uses as much as digits as its factorization.

121543985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24308802.

The product of its digits is 43200, while the sum is 38.

The square root of 121543985 is about 11024.6988621005. The cubic root of 121543985 is about 495.3488477242.

The spelling of 121543985 in words is "one hundred twenty-one million, five hundred forty-three thousand, nine hundred eighty-five".