121730561 has 4 divisors (see below), whose sum is σ = 122410800. Its totient is φ = 121050324.

The previous prime is 121730537. The next prime is 121730569. The reversal of 121730561 is 165037121.

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 not a de Polignac number, because 121730561 - 2²² = 117536257 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 121730561.

It is not an unprimeable number, because it can be changed into a prime (121730569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 339851 + ... + 340208.

It is an arithmetic number, because the mean of its divisors is an integer number (30602700).

Almost surely, 2^121730561 is an apocalyptic number.

It is an amenable number.

121730561 is a deficient number, since it is larger than the sum of its proper divisors (680239).

121730561 is an equidigital number, since it uses as much as digits as its factorization.

121730561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 680238.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 121730561 is about 11033.1573450214. The cubic root of 121730561 is about 495.6021797643.

Adding to 121730561 its reverse (165037121), we get a palindrome (286767682).

The spelling of 121730561 in words is "one hundred twenty-one million, seven hundred thirty thousand, five hundred sixty-one".