21763478285 has 8 divisors (see below), whose sum is σ = 27652419576. Its totient is φ = 16386618880.

The previous prime is 21763478201. The next prime is 21763478299. The reversal of 21763478285 is 58287436712.

It can be written as a sum of positive squares in 4 ways, for example, as 143304841 + 21620173444 = 11971^2 + 147038^2 .

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

It is not a de Polignac number, because 21763478285 - 2²² = 21759283981 is a prime.

It is a super-3 number, since 3×21763478285³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 128020376 + ... + 128020545.

It is an arithmetic number, because the mean of its divisors is an integer number (3456552447).

Almost surely, 2^21763478285 is an apocalyptic number.

It is an amenable number.

21763478285 is a deficient number, since it is larger than the sum of its proper divisors (5888941291).

21763478285 is a wasteful number, since it uses less digits than its factorization.

21763478285 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256040943.

The product of its digits is 4515840, while the sum is 53.

The spelling of 21763478285 in words is "twenty-one billion, seven hundred sixty-three million, four hundred seventy-eight thousand, two hundred eighty-five".