121397421357 has 10 divisors (see below), whose sum is σ = 181346765358. Its totient is φ = 80931614184.

The previous prime is 121397421317. The next prime is 121397421371. The reversal of 121397421357 is 753124793121.

121397421357 is a `hidden beast` number, since 1 + 213 + 9 + 7 + 421 + 3 + 5 + 7 = 666.

It can be written as a sum of positive squares in only one way, i.e., 88669355076 + 32728066281 = 297774^2 + 180909^2 .

It is not a de Polignac number, because 121397421357 - 2¹⁵ = 121397388589 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121397421317) 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 9 ways as a sum of consecutive naturals, for example, 749366718 + ... + 749366879.

Almost surely, 2^121397421357 is an apocalyptic number.

It is an amenable number.

121397421357 is a deficient number, since it is larger than the sum of its proper divisors (59949344001).

121397421357 is an equidigital number, since it uses as much as digits as its factorization.

121397421357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1498733609 (or 1498733600 counting only the distinct ones).

The product of its digits is 317520, while the sum is 45.

The spelling of 121397421357 in words is "one hundred twenty-one billion, three hundred ninety-seven million, four hundred twenty-one thousand, three hundred fifty-seven".