21211000019 has 4 divisors (see below), whose sum is σ = 23139272760. Its totient is φ = 19282727280.

The previous prime is 21210999989. The next prime is 21211000073. The reversal of 21211000019 is 91000011212.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21211000019 is a prime.

It is a super-2 number, since 2×21211000019² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21210999970 and 21211000006.

It is not an unprimeable number, because it can be changed into a prime (21211000319) 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, 964136354 + ... + 964136375.

It is an arithmetic number, because the mean of its divisors is an integer number (5784818190).

Almost surely, 2^21211000019 is an apocalyptic number.

21211000019 is a deficient number, since it is larger than the sum of its proper divisors (1928272741).

21211000019 is a wasteful number, since it uses less digits than its factorization.

21211000019 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1928272740.

The product of its (nonzero) digits is 36, while the sum is 17.

The spelling of 21211000019 in words is "twenty-one billion, two hundred eleven million, nineteen", and thus it is an aban number.