214645721 has 2 divisors, whose sum is σ = 214645722. Its totient is φ = 214645720.

The previous prime is 214645703. The next prime is 214645799. The reversal of 214645721 is 127546412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 154753600 + 59892121 = 12440^2 + 7739^2 .

It is a cyclic number.

It is not a de Polignac number, because 214645721 - 2⁶ = 214645657 is a prime.

It is not a weakly prime, because it can be changed into another prime (214645021) 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, 107322860 + 107322861.

It is an arithmetic number, because the mean of its divisors is an integer number (107322861).

Almost surely, 2^214645721 is an apocalyptic number.

It is an amenable number.

214645721 is a deficient number, since it is larger than the sum of its proper divisors (1).

214645721 is an equidigital number, since it uses as much as digits as its factorization.

214645721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 13440, while the sum is 32.

The square root of 214645721 is about 14650.7925041617. The cubic root of 214645721 is about 598.7434080948.

The spelling of 214645721 in words is "two hundred fourteen million, six hundred forty-five thousand, seven hundred twenty-one".