215670655511 has 4 divisors (see below), whose sum is σ = 215734599192. Its totient is φ = 215606711832.

The previous prime is 215670655481. The next prime is 215670655631. The reversal of 215670655511 is 115556076512.

215670655511 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 215670655511 - 2¹⁰ = 215670654487 is a prime.

It is a super-2 number, since 2×215670655511² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215670655111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31966781 + ... + 31973526.

It is an arithmetic number, because the mean of its divisors is an integer number (53933649798).

Almost surely, 2^215670655511 is an apocalyptic number.

215670655511 is a deficient number, since it is larger than the sum of its proper divisors (63943681).

215670655511 is an equidigital number, since it uses as much as digits as its factorization.

215670655511 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63943680.

The product of its (nonzero) digits is 315000, while the sum is 44.

The spelling of 215670655511 in words is "two hundred fifteen billion, six hundred seventy million, six hundred fifty-five thousand, five hundred eleven".