243121421401 has 2 divisors, whose sum is σ = 243121421402. Its totient is φ = 243121421400.

The previous prime is 243121421383. The next prime is 243121421423. The reversal of 243121421401 is 104124121342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216877421401 + 26244000000 = 465701^2 + 162000^2 .

It is a cyclic number.

It is not a de Polignac number, because 243121421401 - 2⁷ = 243121421273 is a prime.

It is not a weakly prime, because it can be changed into another prime (243121421461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121560710700 + 121560710701.

It is an arithmetic number, because the mean of its divisors is an integer number (121560710701).

Almost surely, 2^243121421401 is an apocalyptic number.

It is an amenable number.

243121421401 is a deficient number, since it is larger than the sum of its proper divisors (1).

243121421401 is an equidigital number, since it uses as much as digits as its factorization.

243121421401 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 25.

Adding to 243121421401 its reverse (104124121342), we get a palindrome (347245542743).

The spelling of 243121421401 in words is "two hundred forty-three billion, one hundred twenty-one million, four hundred twenty-one thousand, four hundred one".