111781129420801 has 2 divisors, whose sum is σ = 111781129420802. Its totient is φ = 111781129420800.

The previous prime is 111781129420799. The next prime is 111781129420847. The reversal of 111781129420801 is 108024921187111.

It is an a-pointer prime, because the next prime (111781129420847) can be obtained adding 111781129420801 to its sum of digits (46).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 110355529240576 + 1425600180225 = 10505024^2 + 1193985^2 .

It is an emirp because it is prime and its reverse (108024921187111) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 111781129420801 - 2¹ = 111781129420799 is a prime.

Together with 111781129420799, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (111781129420871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55890564710400 + 55890564710401.

It is an arithmetic number, because the mean of its divisors is an integer number (55890564710401).

Almost surely, 2^{111781129420801} is an apocalyptic number.

It is an amenable number.

111781129420801 is a deficient number, since it is larger than the sum of its proper divisors (1).

111781129420801 is an equidigital number, since it uses as much as digits as its factorization.

111781129420801 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 64512, while the sum is 46.

The spelling of 111781129420801 in words is "one hundred eleven trillion, seven hundred eighty-one billion, one hundred twenty-nine million, four hundred twenty thousand, eight hundred one".