21222162672 has 80 divisors (see below), whose sum is σ = 56304253440. Its totient is φ = 6884732416.

The previous prime is 21222162667. The next prime is 21222162679. The reversal of 21222162672 is 27626122212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222162679) 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, 377548 + ... + 430100.

It is an arithmetic number, because the mean of its divisors is an integer number (703803168).

Almost surely, 2^21222162672 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21222162672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28152126720).

21222162672 is an abundant number, since it is smaller than the sum of its proper divisors (35082090768).

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

21222162672 is a wasteful number, since it uses less digits than its factorization.

21222162672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52790 (or 52784 counting only the distinct ones).

The product of its digits is 16128, while the sum is 33.

Adding to 21222162672 its reverse (27626122212), we get a palindrome (48848284884).

The spelling of 21222162672 in words is "twenty-one billion, two hundred twenty-two million, one hundred sixty-two thousand, six hundred seventy-two".