20213559681 has 16 divisors (see below), whose sum is σ = 30820809600. Its totient is φ = 11543407488.

The previous prime is 20213559673. The next prime is 20213559731. The reversal of 20213559681 is 18695531202.

It is not a de Polignac number, because 20213559681 - 2³ = 20213559673 is a prime.

It is a super-2 number, since 2×20213559681² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20213559481) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 265326 + ... + 332903.

It is an arithmetic number, because the mean of its divisors is an integer number (1926300600).

Almost surely, 2^20213559681 is an apocalyptic number.

20213559681 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20213559681 is a deficient number, since it is larger than the sum of its proper divisors (10607249919).

20213559681 is a wasteful number, since it uses less digits than its factorization.

20213559681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 599848.

The product of its (nonzero) digits is 129600, while the sum is 42.

The spelling of 20213559681 in words is "twenty billion, two hundred thirteen million, five hundred fifty-nine thousand, six hundred eighty-one".