21012212203 has 2 divisors, whose sum is σ = 21012212204. Its totient is φ = 21012212202.

The previous prime is 21012212159. The next prime is 21012212227. The reversal of 21012212203 is 30221221012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21012212203 - 2¹⁷ = 21012081131 is a prime.

It is a super-2 number, since 2×21012212203² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21012210203) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506106101 + 10506106102.

It is an arithmetic number, because the mean of its divisors is an integer number (10506106102).

Almost surely, 2^21012212203 is an apocalyptic number.

21012212203 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012212203 is an equidigital number, since it uses as much as digits as its factorization.

21012212203 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21012212203 its reverse (30221221012), we get a palindrome (51233433215).

The spelling of 21012212203 in words is "twenty-one billion, twelve million, two hundred twelve thousand, two hundred three".