21161016642 has 48 divisors (see below), whose sum is σ = 44950332960. Its totient is φ = 6622834176.

The previous prime is 21161016599. The next prime is 21161016649. The reversal of 21161016642 is 24661016112.

It is not an unprimeable number, because it can be changed into a prime (21161016649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1448398 + ... + 1462934.

It is an arithmetic number, because the mean of its divisors is an integer number (936465270).

Almost surely, 2^21161016642 is an apocalyptic number.

21161016642 is an abundant number, since it is smaller than the sum of its proper divisors (23789316318).

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

21161016642 is a wasteful number, since it uses less digits than its factorization.

21161016642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14787 (or 14674 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 30.

The spelling of 21161016642 in words is "twenty-one billion, one hundred sixty-one million, sixteen thousand, six hundred forty-two".