689544621 has 24 divisors (see below), whose sum is σ = 1004844984. Its totient is φ = 455639040.

The previous prime is 689544619. The next prime is 689544631. The reversal of 689544621 is 126445986.

689544621 is a `hidden beast` number, since 6 + 89 + 544 + 6 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 481319721 + 208224900 = 21939^2 + 14430^2 .

It is not a de Polignac number, because 689544621 - 2¹ = 689544619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (689544631) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 556815 + ... + 558051.

It is an arithmetic number, because the mean of its divisors is an integer number (41868541).

Almost surely, 2^689544621 is an apocalyptic number.

It is an amenable number.

689544621 is a deficient number, since it is larger than the sum of its proper divisors (315300363).

689544621 is a wasteful number, since it uses less digits than its factorization.

689544621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1741 (or 1738 counting only the distinct ones).

The product of its digits is 414720, while the sum is 45.

The square root of 689544621 is about 26259.1816513767. The cubic root of 689544621 is about 883.4611541940.

The spelling of 689544621 in words is "six hundred eighty-nine million, five hundred forty-four thousand, six hundred twenty-one".