20998564354 has 16 divisors (see below), whose sum is σ = 32676316920. Its totient is φ = 10108510720.

The previous prime is 20998564351. The next prime is 20998564417. The reversal of 20998564354 is 45346589902.

It can be written as a sum of positive squares in 4 ways, for example, as 10630641025 + 10367923329 = 103105^2 + 101823^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20998564295 and 20998564304.

It is not an unprimeable number, because it can be changed into a prime (20998564351) 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, 492337 + ... + 533284.

Almost surely, 2^20998564354 is an apocalyptic number.

20998564354 is a deficient number, since it is larger than the sum of its proper divisors (11677752566).

20998564354 is a wasteful number, since it uses less digits than its factorization.

20998564354 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1026005.

The product of its (nonzero) digits is 9331200, while the sum is 55.

The spelling of 20998564354 in words is "twenty billion, nine hundred ninety-eight million, five hundred sixty-four thousand, three hundred fifty-four".