20645854603 has 8 divisors (see below), whose sum is σ = 22525254720. Its totient is φ = 18766871880.

The previous prime is 20645854571. The next prime is 20645854633. The reversal of 20645854603 is 30645854602.

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

It is a cyclic number.

It is not a de Polignac number, because 20645854603 - 2⁵ = 20645854571 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 20645854603.

It is not an unprimeable number, because it can be changed into a prime (20645854633) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3976 + ... + 203242.

It is an arithmetic number, because the mean of its divisors is an integer number (2815656840).

Almost surely, 2^20645854603 is an apocalyptic number.

20645854603 is a deficient number, since it is larger than the sum of its proper divisors (1879400117).

20645854603 is a wasteful number, since it uses less digits than its factorization.

20645854603 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 208697.

The product of its (nonzero) digits is 691200, while the sum is 43.

Subtracting 20645854603 from its reverse (30645854602), we obtain a palindrome (9999999999).

The spelling of 20645854603 in words is "twenty billion, six hundred forty-five million, eight hundred fifty-four thousand, six hundred three".