20669620 has 24 divisors (see below), whose sum is σ = 45960264. Its totient is φ = 7781376.

The previous prime is 20669611. The next prime is 20669641. The reversal of 20669620 is 2696602.

It can be written as a sum of positive squares in 4 ways, for example, as 6260004 + 14409616 = 2502^2 + 3796^2 .

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 30057 + ... + 30736.

It is an arithmetic number, because the mean of its divisors is an integer number (1915011).

Almost surely, 2^20669620 is an apocalyptic number.

20669620 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20669620 is an abundant number, since it is smaller than the sum of its proper divisors (25290644).

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

20669620 is a wasteful number, since it uses less digits than its factorization.

20669620 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60819 (or 60817 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 20669620 is about 4546.3853774180. The cubic root of 20669620 is about 274.4379484671.

The spelling of 20669620 in words is "twenty million, six hundred sixty-nine thousand, six hundred twenty".