21596609660 has 24 divisors (see below), whose sum is σ = 45359002080. Its totient is φ = 8637477824.

The previous prime is 21596609659. The next prime is 21596609663. The reversal of 21596609660 is 6690669512.

It is a junction number, because it is equal to n+sod(n) for n = 21596609599 and 21596609608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21596609663) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87617 + ... + 225543.

It is an arithmetic number, because the mean of its divisors is an integer number (1889958420).

Almost surely, 2^21596609660 is an apocalyptic number.

21596609660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21596609660 is an abundant number, since it is smaller than the sum of its proper divisors (23762392420).

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

21596609660 is a wasteful number, since it uses less digits than its factorization.

21596609660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145765 (or 145763 counting only the distinct ones).

The product of its (nonzero) digits is 1049760, while the sum is 50.

The spelling of 21596609660 in words is "twenty-one billion, five hundred ninety-six million, six hundred nine thousand, six hundred sixty".