428723987 has 2 divisors, whose sum is σ = 428723988. Its totient is φ = 428723986.

The previous prime is 428723983. The next prime is 428723993. The reversal of 428723987 is 789327824.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 428723987 - 2² = 428723983 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (428723983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 214361993 + 214361994.

It is an arithmetic number, because the mean of its divisors is an integer number (214361994).

Almost surely, 2^428723987 is an apocalyptic number.

428723987 is a deficient number, since it is larger than the sum of its proper divisors (1).

428723987 is an equidigital number, since it uses as much as digits as its factorization.

428723987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1354752, while the sum is 50.

The square root of 428723987 is about 20705.6510885314. The cubic root of 428723987 is about 754.0368913226.

The spelling of 428723987 in words is "four hundred twenty-eight million, seven hundred twenty-three thousand, nine hundred eighty-seven".