121431221447 has 4 divisors (see below), whose sum is σ = 121743384360. Its totient is φ = 121119058536.

The previous prime is 121431221393. The next prime is 121431221449. The reversal of 121431221447 is 744122134121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121431221447 - 2¹² = 121431217351 is a prime.

It is a super-2 number, since 2×121431221447² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121431221449) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 156080873 + ... + 156081650.

It is an arithmetic number, because the mean of its divisors is an integer number (30435846090).

Almost surely, 2^121431221447 is an apocalyptic number.

121431221447 is a deficient number, since it is larger than the sum of its proper divisors (312162913).

121431221447 is an equidigital number, since it uses as much as digits as its factorization.

121431221447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312162912.

The product of its digits is 10752, while the sum is 32.

Adding to 121431221447 its reverse (744122134121), we get a palindrome (865553355568).

The spelling of 121431221447 in words is "one hundred twenty-one billion, four hundred thirty-one million, two hundred twenty-one thousand, four hundred forty-seven".