121623623538 has 16 divisors (see below), whose sum is σ = 243250926336. Its totient is φ = 40540594640.

The previous prime is 121623623531. The next prime is 121623623543. The reversal of 121623623538 is 835326326121.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a self number, because there is not a number n which added to its sum of digits gives 121623623538.

It is not an unprimeable number, because it can be changed into a prime (121623623531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 473695 + ... + 683837.

It is an arithmetic number, because the mean of its divisors is an integer number (15203182896).

Almost surely, 2^121623623538 is an apocalyptic number.

121623623538 is an abundant number, since it is smaller than the sum of its proper divisors (121627302798).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

121623623538 is a wasteful number, since it uses less digits than its factorization.

121623623538 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 306609.

The product of its digits is 311040, while the sum is 42.

Adding to 121623623538 its reverse (835326326121), we get a palindrome (956949949659).

The spelling of 121623623538 in words is "one hundred twenty-one billion, six hundred twenty-three million, six hundred twenty-three thousand, five hundred thirty-eight".