10400001221 has 2 divisors, whose sum is σ = 10400001222. Its totient is φ = 10400001220.

The previous prime is 10400001191. The next prime is 10400001229. The reversal of 10400001221 is 12210000401.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10224040996 + 175960225 = 101114^2 + 13265^2 .

It is a cyclic number.

It is not a de Polignac number, because 10400001221 - 2¹⁰ = 10400000197 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10400001229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5200000610 + 5200000611.

It is an arithmetic number, because the mean of its divisors is an integer number (5200000611).

Almost surely, 2^10400001221 is an apocalyptic number.

It is an amenable number.

10400001221 is a deficient number, since it is larger than the sum of its proper divisors (1).

10400001221 is an equidigital number, since it uses as much as digits as its factorization.

10400001221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 10400001221 its reverse (12210000401), we get a palindrome (22610001622).

The spelling of 10400001221 in words is "ten billion, four hundred million, one thousand, two hundred twenty-one".