21405150228 has 288 divisors, whose sum is σ = 67381638912. Its totient is φ = 5158010880.

The previous prime is 21405150223. The next prime is 21405150229. The reversal of 21405150228 is 82205150412.

It is a junction number, because it is equal to n+sod(n) for n = 21405150195 and 21405150204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21405150223) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 12612676 + ... + 12614372.

It is an arithmetic number, because the mean of its divisors is an integer number (233964024).

Almost surely, 2^21405150228 is an apocalyptic number.

21405150228 is a gapful number since it is divisible by the number (28) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21405150228, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33690819456).

21405150228 is an abundant number, since it is smaller than the sum of its proper divisors (45976488684).

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

21405150228 is a wasteful number, since it uses less digits than its factorization.

21405150228 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1823 (or 1810 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 30.

The spelling of 21405150228 in words is "twenty-one billion, four hundred five million, one hundred fifty thousand, two hundred twenty-eight".