400111121 has 2 divisors, whose sum is σ = 400111122. Its totient is φ = 400111120.

The previous prime is 400111109. The next prime is 400111147. The reversal of 400111121 is 121111004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 321700096 + 78411025 = 17936^2 + 8855^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400111121 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (400111171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200055560 + 200055561.

It is an arithmetic number, because the mean of its divisors is an integer number (200055561).

Almost surely, 2^400111121 is an apocalyptic number.

It is an amenable number.

400111121 is a deficient number, since it is larger than the sum of its proper divisors (1).

400111121 is an equidigital number, since it uses as much as digits as its factorization.

400111121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8, while the sum is 11.

The square root of 400111121 is about 20002.7778320912. Note that the first 3 decimals coincide. The cubic root of 400111121 is about 736.8745222884.

Adding to 400111121 its reverse (121111004), we get a palindrome (521222125).

The spelling of 400111121 in words is "four hundred million, one hundred eleven thousand, one hundred twenty-one".