21601743011 has 4 divisors (see below), whose sum is σ = 21604735152. Its totient is φ = 21598750872.

The previous prime is 21601742993. The next prime is 21601743013. The reversal of 21601743011 is 11034710612.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21601743011 is a prime.

It is a super-2 number, since 2×21601743011² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21601743013) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1485215 + ... + 1499688.

It is an arithmetic number, because the mean of its divisors is an integer number (5401183788).

Almost surely, 2^21601743011 is an apocalyptic number.

21601743011 is a deficient number, since it is larger than the sum of its proper divisors (2992141).

21601743011 is an equidigital number, since it uses as much as digits as its factorization.

21601743011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2992140.

The product of its (nonzero) digits is 1008, while the sum is 26.

The spelling of 21601743011 in words is "twenty-one billion, six hundred one million, seven hundred forty-three thousand, eleven".