20891478653 has 8 divisors (see below), whose sum is σ = 22126115520. Its totient is φ = 19657478080.

The previous prime is 20891478593. The next prime is 20891478659. The reversal of 20891478653 is 35687419802.

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

It is not a de Polignac number, because 20891478653 - 2⁶ = 20891478589 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20891478595 and 20891478604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20891478659) 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, 90623 + ... + 223596.

It is an arithmetic number, because the mean of its divisors is an integer number (2765764440).

It is a 2-persistent number, because it is pandigital, and so is 2⋅20891478653 = 41782957306, but 3⋅20891478653 = 62674435959 is not.

Almost surely, 2^20891478653 is an apocalyptic number.

It is an amenable number.

20891478653 is a deficient number, since it is larger than the sum of its proper divisors (1234636867).

20891478653 is a wasteful number, since it uses less digits than its factorization.

20891478653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 318147.

The product of its (nonzero) digits is 2903040, while the sum is 53.

The spelling of 20891478653 in words is "twenty billion, eight hundred ninety-one million, four hundred seventy-eight thousand, six hundred fifty-three".