215165664 has 216 divisors, whose sum is σ = 724520160. Its totient is φ = 60383232.

The previous prime is 215165659. The next prime is 215165669. The reversal of 215165664 is 466561512.

It is an interprime number because it is at equal distance from previous prime (215165659) and next prime (215165669).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (215165669) 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 35 ways as a sum of consecutive naturals, for example, 1114752 + ... + 1114944.

It is an arithmetic number, because the mean of its divisors is an integer number (3354260).

Almost surely, 2^215165664 is an apocalyptic number.

215165664 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 215165664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (362260080).

215165664 is an abundant number, since it is smaller than the sum of its proper divisors (509354496).

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

215165664 is a wasteful number, since it uses less digits than its factorization.

215165664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302 (or 284 counting only the distinct ones).

The product of its digits is 43200, while the sum is 36.

The square root of 215165664 is about 14668.5263063472. The cubic root of 215165664 is about 599.2264698471.

The spelling of 215165664 in words is "two hundred fifteen million, one hundred sixty-five thousand, six hundred sixty-four".