121211240665 has 8 divisors (see below), whose sum is σ = 147624436800. Its totient is φ = 95521693872.

The previous prime is 121211240663. The next prime is 121211240669. The reversal of 121211240665 is 566042112121.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121211240665 - 2¹ = 121211240663 is a prime.

It is not an unprimeable number, because it can be changed into a prime (121211240663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180911965 + ... + 180912634.

It is an arithmetic number, because the mean of its divisors is an integer number (18453054600).

Almost surely, 2^121211240665 is an apocalyptic number.

It is an amenable number.

121211240665 is a deficient number, since it is larger than the sum of its proper divisors (26413196135).

121211240665 is an equidigital number, since it uses as much as digits as its factorization.

121211240665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 361824671.

The product of its (nonzero) digits is 5760, while the sum is 31.

Adding to 121211240665 its reverse (566042112121), we get a palindrome (687253352786).

The spelling of 121211240665 in words is "one hundred twenty-one billion, two hundred eleven million, two hundred forty thousand, six hundred sixty-five".