400307221 has 2 divisors, whose sum is σ = 400307222. Its totient is φ = 400307220.

The previous prime is 400307209. The next prime is 400307269. The reversal of 400307221 is 122703004.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 208484721 + 191822500 = 14439^2 + 13850^2 .

It is a cyclic number.

It is not a de Polignac number, because 400307221 - 2⁵ = 400307189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (400307291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200153610 + 200153611.

It is an arithmetic number, because the mean of its divisors is an integer number (200153611).

Almost surely, 2^400307221 is an apocalyptic number.

It is an amenable number.

400307221 is a deficient number, since it is larger than the sum of its proper divisors (1).

400307221 is an equidigital number, since it uses as much as digits as its factorization.

400307221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 400307221 is about 20007.6790508045. The cubic root of 400307221 is about 736.9948867616.

The spelling of 400307221 in words is "four hundred million, three hundred seven thousand, two hundred twenty-one".