121312215664 has 20 divisors (see below), whose sum is σ = 247413072040. Its totient is φ = 57463680960.

The previous prime is 121312215623. The next prime is 121312215671. The reversal of 121312215664 is 466512213121.

It is a congruent number.

It is an unprimeable number.

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, 199526367 + ... + 199526974.

It is an arithmetic number, because the mean of its divisors is an integer number (12370653602).

Almost surely, 2^121312215664 is an apocalyptic number.

It is an amenable number.

121312215664 is an abundant number, since it is smaller than the sum of its proper divisors (126100856376).

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

121312215664 is a wasteful number, since it uses less digits than its factorization.

121312215664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 399053368 (or 399053362 counting only the distinct ones).

The product of its digits is 17280, while the sum is 34.

Adding to 121312215664 its reverse (466512213121), we get a palindrome (587824428785).

The spelling of 121312215664 in words is "one hundred twenty-one billion, three hundred twelve million, two hundred fifteen thousand, six hundred sixty-four".