400221473 has 2 divisors, whose sum is σ = 400221474. Its totient is φ = 400221472.

The previous prime is 400221407. The next prime is 400221509. The reversal of 400221473 is 374122004.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 368332864 + 31888609 = 19192^2 + 5647^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-400221473 is a prime.

It is not a weakly prime, because it can be changed into another prime (400221673) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 200110736 + 200110737.

It is an arithmetic number, because the mean of its divisors is an integer number (200110737).

Almost surely, 2^400221473 is an apocalyptic number.

It is an amenable number.

400221473 is a deficient number, since it is larger than the sum of its proper divisors (1).

400221473 is an equidigital number, since it uses as much as digits as its factorization.

400221473 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1344, while the sum is 23.

The square root of 400221473 is about 20005.5360588013. The cubic root of 400221473 is about 736.9422602229.

Adding to 400221473 its reverse (374122004), we get a palindrome (774343477).

The spelling of 400221473 in words is "four hundred million, two hundred twenty-one thousand, four hundred seventy-three".