21601705703 has 4 divisors (see below), whose sum is σ = 21955832088. Its totient is φ = 21247579320.

The previous prime is 21601705693. The next prime is 21601705733. The reversal of 21601705703 is 30750710612.

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-21601705703 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21601705703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21601705733) 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, 177063101 + ... + 177063222.

It is an arithmetic number, because the mean of its divisors is an integer number (5488958022).

Almost surely, 2^21601705703 is an apocalyptic number.

21601705703 is a deficient number, since it is larger than the sum of its proper divisors (354126385).

21601705703 is an equidigital number, since it uses as much as digits as its factorization.

21601705703 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354126384.

The product of its (nonzero) digits is 8820, while the sum is 32.

The spelling of 21601705703 in words is "twenty-one billion, six hundred one million, seven hundred five thousand, seven hundred three".