628022721 has 24 divisors (see below), whose sum is σ = 893993824. Its totient is φ = 392071680.

The previous prime is 628022693. The next prime is 628022729. The reversal of 628022721 is 127220826.

It is not a de Polignac number, because 628022721 - 2⁶ = 628022657 is a prime.

It is not an unprimeable number, because it can be changed into a prime (628022729) 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 23 ways as a sum of consecutive naturals, for example, 181221 + ... + 184653.

Almost surely, 2^628022721 is an apocalyptic number.

It is an amenable number.

628022721 is a deficient number, since it is larger than the sum of its proper divisors (265971103).

628022721 is a wasteful number, since it uses less digits than its factorization.

628022721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3681 (or 3664 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 628022721 is about 25060.3815014856. The cubic root of 628022721 is about 856.3640986283.

The spelling of 628022721 in words is "six hundred twenty-eight million, twenty-two thousand, seven hundred twenty-one".