21421442010 has 64 divisors (see below), whose sum is σ = 52758921600. Its totient is φ = 5563434240.

The previous prime is 21421441999. The next prime is 21421442011. The reversal of 21421442010 is 1024412412.

It is not an unprimeable number, because it can be changed into a prime (21421442011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 426420 + ... + 474000.

It is an arithmetic number, because the mean of its divisors is an integer number (824358150).

Almost surely, 2^21421442010 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21421442010, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26379460800).

21421442010 is an abundant number, since it is smaller than the sum of its proper divisors (31337479590).

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

21421442010 is a wasteful number, since it uses less digits than its factorization.

21421442010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47983.

The product of its (nonzero) digits is 512, while the sum is 21.

Adding to 21421442010 its reverse (1024412412), we get a palindrome (22445854422).

The spelling of 21421442010 in words is "twenty-one billion, four hundred twenty-one million, four hundred forty-two thousand, ten".