21212200001 has 4 divisors (see below), whose sum is σ = 22328631600. Its totient is φ = 20095768404.

The previous prime is 21212199929. The next prime is 21212200013. The reversal of 21212200001 is 10000221212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21212200001 - 2¹⁴ = 21212183617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21212200301) 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, 558215771 + ... + 558215808.

It is an arithmetic number, because the mean of its divisors is an integer number (5582157900).

Almost surely, 2^21212200001 is an apocalyptic number.

It is an amenable number.

21212200001 is a deficient number, since it is larger than the sum of its proper divisors (1116431599).

21212200001 is a wasteful number, since it uses less digits than its factorization.

21212200001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116431598.

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 21212200001 its reverse (10000221212), we get a palindrome (31212421213).

The spelling of 21212200001 in words is "twenty-one billion, two hundred twelve million, two hundred thousand, one".