428792821 has 2 divisors, whose sum is σ = 428792822. Its totient is φ = 428792820.

The previous prime is 428792759. The next prime is 428792839. The reversal of 428792821 is 128297824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 428283025 + 509796 = 20695^2 + 714^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-428792821 is a prime.

It is a super-2 number, since 2×428792821² = 367726566682276082, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (428792321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214396410 + 214396411.

It is an arithmetic number, because the mean of its divisors is an integer number (214396411).

Almost surely, 2^428792821 is an apocalyptic number.

It is an amenable number.

428792821 is a deficient number, since it is larger than the sum of its proper divisors (1).

428792821 is an equidigital number, since it uses as much as digits as its factorization.

428792821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 129024, while the sum is 43.

The square root of 428792821 is about 20707.3132250420. The cubic root of 428792821 is about 754.0772440899.

The spelling of 428792821 in words is "four hundred twenty-eight million, seven hundred ninety-two thousand, eight hundred twenty-one".