20719885 has 8 divisors (see below), whose sum is σ = 24890616. Its totient is φ = 16558080.

The previous prime is 20719841. The next prime is 20719913. The reversal of 20719885 is 58891702.

It can be written as a sum of positive squares in 4 ways, for example, as 13734436 + 6985449 = 3706^2 + 2643^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-20719885 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 5037 + ... + 8173.

It is an arithmetic number, because the mean of its divisors is an integer number (3111327).

Almost surely, 2^20719885 is an apocalyptic number.

It is an amenable number.

20719885 is a deficient number, since it is larger than the sum of its proper divisors (4170731).

20719885 is a wasteful number, since it uses less digits than its factorization.

20719885 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4463.

The product of its (nonzero) digits is 40320, while the sum is 40.

The square root of 20719885 is about 4551.9100386541. The cubic root of 20719885 is about 274.6602305168.

The spelling of 20719885 in words is "twenty million, seven hundred nineteen thousand, eight hundred eighty-five".