21986954660 has 96 divisors (see below), whose sum is σ = 53491536000. Its totient is φ = 7507261440.

The previous prime is 21986954609. The next prime is 21986954681. The reversal of 21986954660 is 6645968912.

It is a junction number, because it is equal to n+sod(n) for n = 21986954596 and 21986954605.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 449066 + ... + 495614.

It is an arithmetic number, because the mean of its divisors is an integer number (557203500).

Almost surely, 2^21986954660 is an apocalyptic number.

21986954660 is a gapful number since it is divisible by the number (20) 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 21986954660, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26745768000).

21986954660 is an abundant number, since it is smaller than the sum of its proper divisors (31504581340).

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

21986954660 is a wasteful number, since it uses less digits than its factorization.

21986954660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 46701 (or 46699 counting only the distinct ones).

The product of its (nonzero) digits is 5598720, while the sum is 56.

The spelling of 21986954660 in words is "twenty-one billion, nine hundred eighty-six million, nine hundred fifty-four thousand, six hundred sixty".