21021403122 has 64 divisors (see below), whose sum is σ = 49204224000. Its totient is φ = 6634106064.

The previous prime is 21021403121. The next prime is 21021403129. The reversal of 21021403122 is 22130412012.

It is a happy number.

21021403122 is a `hidden beast` number, since 210 + 2 + 140 + 312 + 2 = 666.

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

It is a junction number, because it is equal to n+sod(n) for n = 21021403095 and 21021403104.

It is not an unprimeable number, because it can be changed into a prime (21021403121) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1864779 + ... + 1876017.

It is an arithmetic number, because the mean of its divisors is an integer number (768816000).

Almost surely, 2^21021403122 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21021403122, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24602112000).

21021403122 is an abundant number, since it is smaller than the sum of its proper divisors (28182820878).

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

21021403122 is a wasteful number, since it uses less digits than its factorization.

21021403122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13092 (or 13086 counting only the distinct ones).

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

Adding to 21021403122 its reverse (22130412012), we get a palindrome (43151815134).

The spelling of 21021403122 in words is "twenty-one billion, twenty-one million, four hundred three thousand, one hundred twenty-two".