21981706412 has 6 divisors (see below), whose sum is σ = 38467986228. Its totient is φ = 10990853204.

The previous prime is 21981706403. The next prime is 21981706427. The reversal of 21981706412 is 21460718912.

It is a self number, because there is not a number n which added to its sum of digits gives 21981706412.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2747713298 + ... + 2747713305.

It is an arithmetic number, because the mean of its divisors is an integer number (6411331038).

Almost surely, 2^21981706412 is an apocalyptic number.

It is an amenable number.

21981706412 is a deficient number, since it is larger than the sum of its proper divisors (16486279816).

21981706412 is a wasteful number, since it uses less digits than its factorization.

21981706412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5495426607 (or 5495426605 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 41.

The spelling of 21981706412 in words is "twenty-one billion, nine hundred eighty-one million, seven hundred six thousand, four hundred twelve".