31820494689 has 27 divisors (see below), whose sum is σ = 46517551353. Its totient is φ = 20960716032.

The previous prime is 31820494679. The next prime is 31820494691. The reversal of 31820494689 is 98649402813.

The square root of 31820494689 is 178383.

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

31820494689 is a `hidden beast` number, since 318 + 204 + 9 + 46 + 89 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 15716884689 + 16103610000 = 125367^2 + 126900^2 .

It is not a de Polignac number, because 31820494689 - 2¹³ = 31820486497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31820494619) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 51909147 + ... + 51909759.

Almost surely, 2^31820494689 is an apocalyptic number.

31820494689 is the 178383-rd square number.

31820494689 is the 89192-nd centered octagonal number.

It is an amenable number.

31820494689 is a deficient number, since it is larger than the sum of its proper divisors (14697056664).

31820494689 is an frugal number, since it uses more digits than its factorization.

31820494689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1426 (or 713 counting only the distinct ones).

The product of its (nonzero) digits is 2985984, while the sum is 54.

The spelling of 31820494689 in words is "thirty-one billion, eight hundred twenty million, four hundred ninety-four thousand, six hundred eighty-nine".