20021019 has 8 divisors (see below), whose sum is σ = 28265040. Its totient is φ = 12562176.

The previous prime is 20020943. The next prime is 20021021. The reversal of 20021019 is 91012002.

It is a happy number.

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-20021019 is a prime.

It is a super-2 number, since 2×20021019² = 801682403596722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20020989 and 20021007.

It is not an unprimeable number, because it can be changed into a prime (20021059) 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, 196234 + ... + 196335.

It is an arithmetic number, because the mean of its divisors is an integer number (3533130).

Almost surely, 2^20021019 is an apocalyptic number.

20021019 is a deficient number, since it is larger than the sum of its proper divisors (8244021).

20021019 is a wasteful number, since it uses less digits than its factorization.

20021019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 392589.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 20021019 is about 4474.4853335328. The cubic root of 20021019 is about 271.5368189403.

The spelling of 20021019 in words is "twenty million, twenty-one thousand, nineteen".