215665530 has 32 divisors (see below), whose sum is σ = 519934464. Its totient is φ = 57251136.

The previous prime is 215665529. The next prime is 215665531. The reversal of 215665530 is 35566512.

It is an interprime number because it is at equal distance from previous prime (215665529) and next prime (215665531).

It is a junction number, because it is equal to n+sod(n) for n = 215665491 and 215665500.

It is not an unprimeable number, because it can be changed into a prime (215665531) 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 15 ways as a sum of consecutive naturals, for example, 9429 + ... + 22808.

It is an arithmetic number, because the mean of its divisors is an integer number (16247952).

Almost surely, 2^215665530 is an apocalyptic number.

215665530 is an abundant number, since it is smaller than the sum of its proper divisors (304268934).

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

215665530 is a wasteful number, since it uses less digits than its factorization.

215665530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32470.

The product of its (nonzero) digits is 27000, while the sum is 33.

The square root of 215665530 is about 14685.5551478315. Note that the first 3 decimals coincide. The cubic root of 215665530 is about 599.6901455668.

The spelling of 215665530 in words is "two hundred fifteen million, six hundred sixty-five thousand, five hundred thirty".