21987946122 has 32 divisors (see below), whose sum is σ = 44990017920. Its totient is φ = 7162122240.

The previous prime is 21987946067. The next prime is 21987946151. The reversal of 21987946122 is 22164978912.

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, 180247 + ... + 276522.

It is an arithmetic number, because the mean of its divisors is an integer number (1405938060).

Almost surely, 2^21987946122 is an apocalyptic number.

21987946122 is an abundant number, since it is smaller than the sum of its proper divisors (23002071798).

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

21987946122 is a wasteful number, since it uses less digits than its factorization.

21987946122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 456958.

The product of its digits is 870912, while the sum is 51.

The spelling of 21987946122 in words is "twenty-one billion, nine hundred eighty-seven million, nine hundred forty-six thousand, one hundred twenty-two".