21112657642 has 8 divisors (see below), whose sum is σ = 31737684132. Its totient is φ = 10533429600.

The previous prime is 21112657583. The next prime is 21112657681. The reversal of 21112657642 is 24675621112.

It can be written as a sum of positive squares in 2 ways, for example, as 18389800881 + 2722856761 = 135609^2 + 52181^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 11448459 + ... + 11450302.

Almost surely, 2^21112657642 is an apocalyptic number.

21112657642 is a deficient number, since it is larger than the sum of its proper divisors (10625026490).

21112657642 is a wasteful number, since it uses less digits than its factorization.

21112657642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22899224.

The product of its digits is 40320, while the sum is 37.

The spelling of 21112657642 in words is "twenty-one billion, one hundred twelve million, six hundred fifty-seven thousand, six hundred forty-two".