21201210019 has 4 divisors (see below), whose sum is σ = 23128592760. Its totient is φ = 19273827280.

The previous prime is 21201210007. The next prime is 21201210047. The reversal of 21201210019 is 91001210212.

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 21201210019 - 2¹⁹ = 21200685731 is a prime.

It is a super-2 number, since 2×21201210019² (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 = 21201209978 and 21201210005.

It is not an unprimeable number, because it can be changed into a prime (21201280019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 963691354 + ... + 963691375.

It is an arithmetic number, because the mean of its divisors is an integer number (5782148190).

Almost surely, 2^21201210019 is an apocalyptic number.

21201210019 is a deficient number, since it is larger than the sum of its proper divisors (1927382741).

21201210019 is a wasteful number, since it uses less digits than its factorization.

21201210019 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1927382740.

The product of its (nonzero) digits is 72, while the sum is 19.

The spelling of 21201210019 in words is "twenty-one billion, two hundred one million, two hundred ten thousand, nineteen".