111205404721 has 2 divisors, whose sum is σ = 111205404722. Its totient is φ = 111205404720.

The previous prime is 111205404707. The next prime is 111205404733. The reversal of 111205404721 is 127404502111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 107511196321 + 3694208400 = 327889^2 + 60780^2 .

It is a cyclic number.

It is not a de Polignac number, because 111205404721 - 2²³ = 111197016113 is a prime.

It is a super-2 number, since 2×111205404721² (a number of 23 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 111205404721.

It is not a weakly prime, because it can be changed into another prime (111205404701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 55602702360 + 55602702361.

It is an arithmetic number, because the mean of its divisors is an integer number (55602702361).

Almost surely, 2^111205404721 is an apocalyptic number.

It is an amenable number.

111205404721 is a deficient number, since it is larger than the sum of its proper divisors (1).

111205404721 is an equidigital number, since it uses as much as digits as its factorization.

111205404721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2240, while the sum is 28.

Adding to 111205404721 its reverse (127404502111), we get a palindrome (238609906832).

The spelling of 111205404721 in words is "one hundred eleven billion, two hundred five million, four hundred four thousand, seven hundred twenty-one".