21112377643 has 4 divisors (see below), whose sum is σ = 24128431600. Its totient is φ = 18096323688.

The previous prime is 21112377623. The next prime is 21112377653. The reversal of 21112377643 is 34677321112.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21112377643 - 2⁹ = 21112377131 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21112377613) by changing a digit.

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 in 3 ways as a sum of consecutive naturals, for example, 1508026968 + ... + 1508026981.

It is an arithmetic number, because the mean of its divisors is an integer number (6032107900).

Almost surely, 2^21112377643 is an apocalyptic number.

21112377643 is a deficient number, since it is larger than the sum of its proper divisors (3016053957).

21112377643 is an equidigital number, since it uses as much as digits as its factorization.

21112377643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3016053956.

The product of its digits is 42336, while the sum is 37.

Adding to 21112377643 its reverse (34677321112), we get a palindrome (55789698755).

The spelling of 21112377643 in words is "twenty-one billion, one hundred twelve million, three hundred seventy-seven thousand, six hundred forty-three".