20997579283 has 4 divisors (see below), whose sum is σ = 21013946568. Its totient is φ = 20981212000.

The previous prime is 20997579241. The next prime is 20997579293. The reversal of 20997579283 is 38297579902.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20997579283 - 2¹⁷ = 20997448211 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20997579293) 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, 8181718 + ... + 8184283.

It is an arithmetic number, because the mean of its divisors is an integer number (5253486642).

Almost surely, 2^20997579283 is an apocalyptic number.

20997579283 is a deficient number, since it is larger than the sum of its proper divisors (16367285).

20997579283 is a wasteful number, since it uses less digits than its factorization.

20997579283 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16367284.

The product of its (nonzero) digits is 17146080, while the sum is 61.

The spelling of 20997579283 in words is "twenty billion, nine hundred ninety-seven million, five hundred seventy-nine thousand, two hundred eighty-three".