121478399999 has 12 divisors (see below), whose sum is σ = 136045207368. Its totient is φ = 108351225840.

The previous prime is 121478399971. The next prime is 121478400011. The reversal of 121478399999 is 999993874121.

It is not a de Polignac number, because 121478399999 - 2¹⁶ = 121478334463 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121478393999) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9464849 + ... + 9477674.

It is an arithmetic number, because the mean of its divisors is an integer number (11337100614).

Almost surely, 2^121478399999 is an apocalyptic number.

121478399999 is a deficient number, since it is larger than the sum of its proper divisors (14566807369).

121478399999 is a wasteful number, since it uses less digits than its factorization.

121478399999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18942598 (or 18942587 counting only the distinct ones).

The product of its digits is 79361856, while the sum is 71.

The spelling of 121478399999 in words is "one hundred twenty-one billion, four hundred seventy-eight million, three hundred ninety-nine thousand, nine hundred ninety-nine".