21212321010 has 32 divisors (see below), whose sum is σ = 50932348992. Its totient is φ = 5654088000.

The previous prime is 21212320999. The next prime is 21212321023. The reversal of 21212321010 is 1012321212.

21212321010 is an esthetic number in base 10, because in such base its adjacent digits differ by 1.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is an alternating number because its digits alternate between even and odd.

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 89529 + ... + 224588.

It is an arithmetic number, because the mean of its divisors is an integer number (1591635906).

Almost surely, 2^21212321010 is an apocalyptic number.

21212321010 is an abundant number, since it is smaller than the sum of its proper divisors (29720027982).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21212321010 is a wasteful number, since it uses less digits than its factorization.

21212321010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316378.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21212321010 its reverse (1012321212), we get a palindrome (22224642222).

The spelling of 21212321010 in words is "twenty-one billion, two hundred twelve million, three hundred twenty-one thousand, ten".