20996819 has 8 divisors (see below), whose sum is σ = 22333968. Its totient is φ = 19671040.

The previous prime is 20996803. The next prime is 20996849. The reversal of 20996819 is 91869902.

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

It is not a de Polignac number, because 20996819 - 2⁴ = 20996803 is a prime.

It is a super-2 number, since 2×20996819² = 881732816237522, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20996819.

It is not an unprimeable number, because it can be changed into a prime (20996849) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1139 + ... + 6579.

It is an arithmetic number, because the mean of its divisors is an integer number (2791746).

Almost surely, 2^20996819 is an apocalyptic number.

20996819 is a deficient number, since it is larger than the sum of its proper divisors (1337149).

20996819 is a wasteful number, since it uses less digits than its factorization.

20996819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5685.

The product of its (nonzero) digits is 69984, while the sum is 44.

The square root of 20996819 is about 4582.2286062570. The cubic root of 20996819 is about 275.8784865572.

The spelling of 20996819 in words is "twenty million, nine hundred ninety-six thousand, eight hundred nineteen".