3656421220 has 12 divisors (see below), whose sum is σ = 7678484604. Its totient is φ = 1462568480.

The previous prime is 3656421169. The next prime is 3656421221. The reversal of 3656421220 is 221246563.

It can be written as a sum of positive squares in 2 ways, for example, as 1245807616 + 2410613604 = 35296^2 + 49098^2 .

It is a super-2 number, since 2×3656421220² = 26738832276132576800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (3656421221) by changing a digit.

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, 91410511 + ... + 91410550.

It is an arithmetic number, because the mean of its divisors is an integer number (639873717).

Almost surely, 2^3656421220 is an apocalyptic number.

It is an amenable number.

3656421220 is an abundant number, since it is smaller than the sum of its proper divisors (4022063384).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3656421220 is a wasteful number, since it uses less digits than its factorization.

3656421220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182821070 (or 182821068 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 3656421220 is about 60468.3489108145. The cubic root of 3656421220 is about 1540.5840843968.

Adding to 3656421220 its reverse (221246563), we get a palindrome (3877667783).

The spelling of 3656421220 in words is "three billion, six hundred fifty-six million, four hundred twenty-one thousand, two hundred twenty".