21020012020019 has 4 divisors (see below), whose sum is σ = 21042445331544. Its totient is φ = 20997578708496.

The previous prime is 21020012019997. The next prime is 21020012020037. The reversal of 21020012020019 is 91002021002012.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21020012020019 - 2³² = 21015717052723 is a prime.

It is a super-2 number, since 2×21020012020019² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21020012020069) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11216654357 + ... + 11216656230.

It is an arithmetic number, because the mean of its divisors is an integer number (5260611332886).

Almost surely, 2^{21020012020019} is an apocalyptic number.

21020012020019 is a deficient number, since it is larger than the sum of its proper divisors (22433311525).

21020012020019 is an equidigital number, since it uses as much as digits as its factorization.

21020012020019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22433311524.

The product of its (nonzero) digits is 144, while the sum is 20.

The spelling of 21020012020019 in words is "twenty-one trillion, twenty billion, twelve million, twenty thousand, nineteen".