21106494672 has 80 divisors (see below), whose sum is σ = 55809606528. Its totient is φ = 6871633920.

The previous prime is 21106494593. The next prime is 21106494691. The reversal of 21106494672 is 27649460112.

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, 331672 + ... + 390152.

Almost surely, 2^21106494672 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 21106494672, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27904803264).

21106494672 is an abundant number, since it is smaller than the sum of its proper divisors (34703111856).

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

21106494672 is a wasteful number, since it uses less digits than its factorization.

21106494672 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58668 (or 58662 counting only the distinct ones).

The product of its (nonzero) digits is 145152, while the sum is 42.

The spelling of 21106494672 in words is "twenty-one billion, one hundred six million, four hundred ninety-four thousand, six hundred seventy-two".