20841830689 has 9 divisors (see below), whose sum is σ = 21540460851. Its totient is φ = 20165182560.

The previous prime is 20841830657. The next prime is 20841830701. The reversal of 20841830689 is 98603814802.

The square root of 20841830689 is 144367.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2506504225 + 18335326464 = 50065^2 + 135408^2 .

It is not a de Polignac number, because 20841830689 - 2⁵ = 20841830657 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20841800689) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 4473049 + ... + 4477705.

It is an arithmetic number, because the mean of its divisors is an integer number (2393384539).

Almost surely, 2^20841830689 is an apocalyptic number.

20841830689 is the 144367-th square number.

20841830689 is the 72184-th centered octagonal number.

It is an amenable number.

20841830689 is a deficient number, since it is larger than the sum of its proper divisors (698630162).

20841830689 is an frugal number, since it uses more digits than its factorization.

20841830689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9376 (or 4688 counting only the distinct ones).

The product of its (nonzero) digits is 663552, while the sum is 49.

Multiplying 20841830689 by its sum of digits (49), we get a square (1021249703761 = 1010569²).

The spelling of 20841830689 in words is "twenty billion, eight hundred forty-one million, eight hundred thirty thousand, six hundred eighty-nine".