164015655521 has 4 divisors (see below), whose sum is σ = 164019736212. Its totient is φ = 164011574832.

The previous prime is 164015655509. The next prime is 164015655523. The reversal of 164015655521 is 125556510461.

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 132251504896 + 31764150625 = 363664^2 + 178225^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-164015655521 is a prime.

It is a super-2 number, since 2×164015655521² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (164015655523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1979450 + ... + 2060643.

It is an arithmetic number, because the mean of its divisors is an integer number (41004934053).

Almost surely, 2^164015655521 is an apocalyptic number.

It is an amenable number.

164015655521 is a deficient number, since it is larger than the sum of its proper divisors (4080691).

164015655521 is an equidigital number, since it uses as much as digits as its factorization.

164015655521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4080690.

The product of its (nonzero) digits is 180000, while the sum is 41.

The spelling of 164015655521 in words is "one hundred sixty-four billion, fifteen million, six hundred fifty-five thousand, five hundred twenty-one".