21633225016 has 64 divisors (see below), whose sum is σ = 46772056800. Its totient is φ = 9291583488.

The previous prime is 21633224993. The next prime is 21633225049. The reversal of 21633225016 is 61052233612.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88611 + ... + 226093.

Almost surely, 2^21633225016 is an apocalyptic number.

21633225016 is a gapful number since it is divisible by the number (26) 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 21633225016, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23386028400).

21633225016 is an abundant number, since it is smaller than the sum of its proper divisors (25138831784).

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

21633225016 is a wasteful number, since it uses less digits than its factorization.

21633225016 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137608 (or 137604 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 31.

Adding to 21633225016 its reverse (61052233612), we get a palindrome (82685458628).

The spelling of 21633225016 in words is "twenty-one billion, six hundred thirty-three million, two hundred twenty-five thousand, sixteen".