20980729481 has 4 divisors (see below), whose sum is σ = 21068515200. Its totient is φ = 20892943764.

The previous prime is 20980729477. The next prime is 20980729493. The reversal of 20980729481 is 18492708902.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20980729481 - 2² = 20980729477 is a prime.

It is a super-2 number, since 2×20980729481² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20980729981) 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, 43892501 + ... + 43892978.

It is an arithmetic number, because the mean of its divisors is an integer number (5267128800).

Almost surely, 2^20980729481 is an apocalyptic number.

It is an amenable number.

20980729481 is a deficient number, since it is larger than the sum of its proper divisors (87785719).

20980729481 is an equidigital number, since it uses as much as digits as its factorization.

20980729481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87785718.

The product of its (nonzero) digits is 580608, while the sum is 50.

The spelling of 20980729481 in words is "twenty billion, nine hundred eighty million, seven hundred twenty-nine thousand, four hundred eighty-one".