20661266503 has 8 divisors (see below), whose sum is σ = 20713770000. Its totient is φ = 20608823040.

The previous prime is 20661266473. The next prime is 20661266513. The reversal of 20661266503 is 30566216602.

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 20661266503 - 2⁵ = 20661266471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661266513) 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 7 ways as a sum of consecutive naturals, for example, 719073 + ... + 747253.

It is an arithmetic number, because the mean of its divisors is an integer number (2589221250).

Almost surely, 2^20661266503 is an apocalyptic number.

20661266503 is a deficient number, since it is larger than the sum of its proper divisors (52503497).

20661266503 is a wasteful number, since it uses less digits than its factorization.

20661266503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30017.

The product of its (nonzero) digits is 77760, while the sum is 37.

The spelling of 20661266503 in words is "twenty billion, six hundred sixty-one million, two hundred sixty-six thousand, five hundred three".