400442197 has 2 divisors, whose sum is σ = 400442198. Its totient is φ = 400442196.

The previous prime is 400442173. The next prime is 400442243. The reversal of 400442197 is 791244004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 399440196 + 1002001 = 19986^2 + 1001^2 .

It is a cyclic number.

It is not a de Polignac number, because 400442197 - 2²³ = 392053589 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400442597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200221098 + 200221099.

It is an arithmetic number, because the mean of its divisors is an integer number (200221099).

Almost surely, 2^400442197 is an apocalyptic number.

It is an amenable number.

400442197 is a deficient number, since it is larger than the sum of its proper divisors (1).

400442197 is an equidigital number, since it uses as much as digits as its factorization.

400442197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 400442197 is about 20011.0518714035. The cubic root of 400442197 is about 737.0777110177.

The spelling of 400442197 in words is "four hundred million, four hundred forty-two thousand, one hundred ninety-seven".