5215656181 has 4 divisors (see below), whose sum is σ = 5228794252. Its totient is φ = 5202518112.

The previous prime is 5215656133. The next prime is 5215656247. The reversal of 5215656181 is 1816565125.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3111966225 + 2103689956 = 55785^2 + 45866^2 .

It is a cyclic number.

It is not a de Polignac number, because 5215656181 - 2¹³ = 5215647989 is a prime.

It is a super-2 number, since 2×5215656181² = 54406138796807009522, which contains 22 as substring.

It is the 72220-th Hogben number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (5215659181) by changing a digit.

It is a nontrivial repunit in base 72219.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6568440 + ... + 6569233.

It is an arithmetic number, because the mean of its divisors is an integer number (1307198563).

Almost surely, 2^5215656181 is an apocalyptic number.

It is an amenable number.

5215656181 is a deficient number, since it is larger than the sum of its proper divisors (13138071).

5215656181 is a wasteful number, since it uses less digits than its factorization.

5215656181 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13138070.

The product of its digits is 72000, while the sum is 40.

The square root of 5215656181 is about 72219.5000051925. The cubic root of 5215656181 is about 1734.2151860800.

The spelling of 5215656181 in words is "five billion, two hundred fifteen million, six hundred fifty-six thousand, one hundred eighty-one".