21820216006 has 32 divisors (see below), whose sum is σ = 35311127040. Its totient is φ = 10075497600.

The previous prime is 21820216003. The next prime is 21820216007. The reversal of 21820216006 is 60061202812.

It is a super-2 number, since 2×21820216006² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21820216003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 487935 + ... + 530773.

It is an arithmetic number, because the mean of its divisors is an integer number (1103472720).

Almost surely, 2^21820216006 is an apocalyptic number.

21820216006 is a deficient number, since it is larger than the sum of its proper divisors (13490911034).

21820216006 is a wasteful number, since it uses less digits than its factorization.

21820216006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 43140.

The product of its (nonzero) digits is 2304, while the sum is 28.

Adding to 21820216006 its reverse (60061202812), we get a palindrome (81881418818).

The spelling of 21820216006 in words is "twenty-one billion, eight hundred twenty million, two hundred sixteen thousand, six".