20689700 has 18 divisors (see below), whose sum is σ = 44896866. Its totient is φ = 8275840.

The previous prime is 20689699. The next prime is 20689703. The reversal of 20689700 is 798602.

It can be written as a sum of positive squares in 3 ways, for example, as 565504 + 20124196 = 752^2 + 4486^2 .

It is not an unprimeable number, because it can be changed into a prime (20689703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 103349 + ... + 103548.

Almost surely, 2^20689700 is an apocalyptic number.

20689700 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20689700 is an abundant number, since it is smaller than the sum of its proper divisors (24207166).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20689700 is a wasteful number, since it uses less digits than its factorization.

20689700 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 206911 (or 206904 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 32.

The square root of 20689700 is about 4548.5931891080. The cubic root of 20689700 is about 274.5267894885.

The spelling of 20689700 in words is "twenty million, six hundred eighty-nine thousand, seven hundred".