428887770821 has 2 divisors, whose sum is σ = 428887770822. Its totient is φ = 428887770820.

The previous prime is 428887770799. The next prime is 428887770841. The reversal of 428887770821 is 128077788824.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 303457756900 + 125430013921 = 550870^2 + 354161^2 .

It is a cyclic number.

It is not a de Polignac number, because 428887770821 - 2⁶ = 428887770757 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (428887770841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214443885410 + 214443885411.

It is an arithmetic number, because the mean of its divisors is an integer number (214443885411).

Almost surely, 2^428887770821 is an apocalyptic number.

It is an amenable number.

428887770821 is a deficient number, since it is larger than the sum of its proper divisors (1).

428887770821 is an equidigital number, since it uses as much as digits as its factorization.

428887770821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22478848, while the sum is 62.

The spelling of 428887770821 in words is "four hundred twenty-eight billion, eight hundred eighty-seven million, seven hundred seventy thousand, eight hundred twenty-one".