217331530 has 16 divisors (see below), whose sum is σ = 421289064. Its totient is φ = 80245440.

The previous prime is 217331501. The next prime is 217331551. The reversal of 217331530 is 35133712.

It can be written as a sum of positive squares in 4 ways, for example, as 118309129 + 99022401 = 10877^2 + 9951^2 .

It is a junction number, because it is equal to n+sod(n) for n = 217331495 and 217331504.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 835761 + ... + 836020.

Almost surely, 2^217331530 is an apocalyptic number.

217331530 is a deficient number, since it is larger than the sum of its proper divisors (203957534).

217331530 is a wasteful number, since it uses less digits than its factorization.

217331530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1671801.

The product of its (nonzero) digits is 1890, while the sum is 25.

The square root of 217331530 is about 14742.1684293729. The cubic root of 217331530 is about 601.2303733924.

The spelling of 217331530 in words is "two hundred seventeen million, three hundred thirty-one thousand, five hundred thirty".