21221420310 has 64 divisors (see below), whose sum is σ = 57549657600. Its totient is φ = 5563125216.

The previous prime is 21221420303. The next prime is 21221420323. The reversal of 21221420310 is 1302412212.

It is a happy number.

21221420310 is a `hidden beast` number, since 21 + 221 + 420 + 3 + 1 + 0 = 666.

It is a super-2 number, since 2×21221420310² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent 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 31 ways as a sum of consecutive naturals, for example, 650154 + ... + 682013.

It is an arithmetic number, because the mean of its divisors is an integer number (899213400).

Almost surely, 2^21221420310 is an apocalyptic number.

21221420310 is an abundant number, since it is smaller than the sum of its proper divisors (36328237290).

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

21221420310 is a wasteful number, since it uses less digits than its factorization.

21221420310 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1332242 (or 1332236 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

Adding to 21221420310 its reverse (1302412212), we get a palindrome (22523832522).

The spelling of 21221420310 in words is "twenty-one billion, two hundred twenty-one million, four hundred twenty thousand, three hundred ten".