400242197 has 2 divisors, whose sum is σ = 400242198. Its totient is φ = 400242196.

The previous prime is 400242187. The next prime is 400242217. The reversal of 400242197 is 791242004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 383807281 + 16434916 = 19591^2 + 4054^2 .

It is a cyclic number.

It is not a de Polignac number, because 400242197 - 2⁴ = 400242181 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400242127) 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, 200121098 + 200121099.

It is an arithmetic number, because the mean of its divisors is an integer number (200121099).

Almost surely, 2^400242197 is an apocalyptic number.

It is an amenable number.

400242197 is a deficient number, since it is larger than the sum of its proper divisors (1).

400242197 is an equidigital number, since it uses as much as digits as its factorization.

400242197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 400242197 is about 20006.0540087245. The cubic root of 400242197 is about 736.9549799533.

The spelling of 400242197 in words is "four hundred million, two hundred forty-two thousand, one hundred ninety-seven".