428365681 has 2 divisors, whose sum is σ = 428365682. Its totient is φ = 428365680.

The previous prime is 428365669. The next prime is 428365723. The reversal of 428365681 is 186563824.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 373842225 + 54523456 = 19335^2 + 7384^2 .

It is a cyclic number.

It is not a de Polignac number, because 428365681 - 2¹⁵ = 428332913 is a prime.

It is a super-2 number, since 2×428365681² = 366994313317187522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (428365181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214182840 + 214182841.

It is an arithmetic number, because the mean of its divisors is an integer number (214182841).

Almost surely, 2^428365681 is an apocalyptic number.

It is an amenable number.

428365681 is a deficient number, since it is larger than the sum of its proper divisors (1).

428365681 is an equidigital number, since it uses as much as digits as its factorization.

428365681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 276480, while the sum is 43.

The square root of 428365681 is about 20696.9969077642. The cubic root of 428365681 is about 753.8267707073.

The spelling of 428365681 in words is "four hundred twenty-eight million, three hundred sixty-five thousand, six hundred eighty-one".