400231009 has 2 divisors, whose sum is σ = 400231010. Its totient is φ = 400231008.

The previous prime is 400230997. The next prime is 400231019. The reversal of 400231009 is 900132004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 298321984 + 101909025 = 17272^2 + 10095^2 .

It is a cyclic number.

It is not a de Polignac number, because 400231009 - 2⁵ = 400230977 is a prime.

It is not a weakly prime, because it can be changed into another prime (400231019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200115504 + 200115505.

It is an arithmetic number, because the mean of its divisors is an integer number (200115505).

Almost surely, 2^400231009 is an apocalyptic number.

It is an amenable number.

400231009 is a deficient number, since it is larger than the sum of its proper divisors (1).

400231009 is an equidigital number, since it uses as much as digits as its factorization.

400231009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 216, while the sum is 19.

The square root of 400231009 is about 20005.7743914101. The cubic root of 400231009 is about 736.9481131702.

The spelling of 400231009 in words is "four hundred million, two hundred thirty-one thousand, nine".