400431197 has 2 divisors, whose sum is σ = 400431198. Its totient is φ = 400431196.

The previous prime is 400431193. The next prime is 400431233. The reversal of 400431197 is 791134004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 332187076 + 68244121 = 18226^2 + 8261^2 .

It is a cyclic number.

It is not a de Polignac number, because 400431197 - 2² = 400431193 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400431191) 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, 200215598 + 200215599.

It is an arithmetic number, because the mean of its divisors is an integer number (200215599).

Almost surely, 2^400431197 is an apocalyptic number.

It is an amenable number.

400431197 is a deficient number, since it is larger than the sum of its proper divisors (1).

400431197 is an equidigital number, since it uses as much as digits as its factorization.

400431197 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 400431197 is about 20010.7770213952. Note that the first 3 decimals coincide. The cubic root of 400431197 is about 737.0709618713.

The spelling of 400431197 in words is "four hundred million, four hundred thirty-one thousand, one hundred ninety-seven".