406458721 has 2 divisors, whose sum is σ = 406458722. Its totient is φ = 406458720.

The previous prime is 406458641. The next prime is 406458761. The reversal of 406458721 is 127854604.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 259564321 + 146894400 = 16111^2 + 12120^2 .

It is a cyclic number.

It is not a de Polignac number, because 406458721 - 2¹³ = 406450529 is a prime.

It is not a weakly prime, because it can be changed into another prime (406458761) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203229360 + 203229361.

It is an arithmetic number, because the mean of its divisors is an integer number (203229361).

Almost surely, 2^406458721 is an apocalyptic number.

It is an amenable number.

406458721 is a deficient number, since it is larger than the sum of its proper divisors (1).

406458721 is an equidigital number, since it uses as much as digits as its factorization.

406458721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 53760, while the sum is 37.

The square root of 406458721 is about 20160.8214366379. The cubic root of 406458721 is about 740.7508333638.

The spelling of 406458721 in words is "four hundred six million, four hundred fifty-eight thousand, seven hundred twenty-one".