689021221 has 16 divisors (see below), whose sum is σ = 813800448. Its totient is φ = 570873600.

The previous prime is 689021219. The next prime is 689021227. The reversal of 689021221 is 122120986.

It is a cyclic number.

It is not a de Polignac number, because 689021221 - 2¹ = 689021219 is a prime.

It is a super-3 number, since 3×689021221³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689021227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 294171 + ... + 296503.

It is an arithmetic number, because the mean of its divisors is an integer number (50862528).

Almost surely, 2^689021221 is an apocalyptic number.

It is an amenable number.

689021221 is a deficient number, since it is larger than the sum of its proper divisors (124779227).

689021221 is a wasteful number, since it uses less digits than its factorization.

689021221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3732.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 689021221 is about 26249.2137215575. The cubic root of 689021221 is about 883.2375667232.

The spelling of 689021221 in words is "six hundred eighty-nine million, twenty-one thousand, two hundred twenty-one".