20545819 has 8 divisors (see below), whose sum is σ = 23701248. Its totient is φ = 17445480.

The previous prime is 20545817. The next prime is 20545829. The reversal of 20545819 is 91854502.

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

It is a cyclic number.

It is not a de Polignac number, because 20545819 - 2¹ = 20545817 is a prime.

It is a super-2 number, since 2×20545819² = 844261356761522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20545817) 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 7 ways as a sum of consecutive naturals, for example, 12967 + ... + 14464.

It is an arithmetic number, because the mean of its divisors is an integer number (2962656).

Almost surely, 2^20545819 is an apocalyptic number.

20545819 is a deficient number, since it is larger than the sum of its proper divisors (3155429).

20545819 is a wasteful number, since it uses less digits than its factorization.

20545819 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27545.

The product of its (nonzero) digits is 14400, while the sum is 34.

The square root of 20545819 is about 4532.7496070266. The cubic root of 20545819 is about 273.8889341533. Note that the first 3 decimals are identical.

The spelling of 20545819 in words is "twenty million, five hundred forty-five thousand, eight hundred nineteen".