21195671616 has 336 divisors, whose sum is σ = 73393157760. Its totient is φ = 5713182720.

The previous prime is 21195671603. The next prime is 21195671701. The reversal of 21195671616 is 61617659112.

21195671616 is a `hidden beast` number, since 21 + 1 + 9 + 5 + 6 + 7 + 1 + 616 = 666.

It is a tau number, because it is divible by the number of its divisors (336).

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25816486 + ... + 25817306.

Almost surely, 2^21195671616 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 21195671616, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36696578880).

21195671616 is an abundant number, since it is smaller than the sum of its proper divisors (52197486144).

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

21195671616 is a wasteful number, since it uses less digits than its factorization.

21195671616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1202 (or 1189 counting only the distinct ones).

The product of its digits is 136080, while the sum is 45.

The spelling of 21195671616 in words is "twenty-one billion, one hundred ninety-five million, six hundred seventy-one thousand, six hundred sixteen".