428321691 has 18 divisors (see below), whose sum is σ = 719697732. Its totient is φ = 244755000.

The previous prime is 428321653. The next prime is 428321701. The reversal of 428321691 is 196123824.

It is not a de Polignac number, because 428321691 - 2⁶ = 428321627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (428321791) 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 in 17 ways as a sum of consecutive naturals, for example, 485185 + ... + 486066.

Almost surely, 2^428321691 is an apocalyptic number.

428321691 is a deficient number, since it is larger than the sum of its proper divisors (291376041).

428321691 is a wasteful number, since it uses less digits than its factorization.

428321691 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 971271 (or 971261 counting only the distinct ones).

The product of its digits is 20736, while the sum is 36.

The square root of 428321691 is about 20695.9341659177. The cubic root of 428321691 is about 753.8009656717.

The spelling of 428321691 in words is "four hundred twenty-eight million, three hundred twenty-one thousand, six hundred ninety-one".