217532020 has 24 divisors (see below), whose sum is σ = 461953800. Its totient is φ = 86034432.

The previous prime is 217532011. The next prime is 217532047. The reversal of 217532020 is 20235712.

It can be written as a sum of positive squares in 4 ways, for example, as 5654884 + 211877136 = 2378^2 + 14556^2 .

It is a junction number, because it is equal to n+sod(n) for n = 217531982 and 217532000.

It is a congruent number.

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, 59325 + ... + 62884.

It is an arithmetic number, because the mean of its divisors is an integer number (19248075).

Almost surely, 2^217532020 is an apocalyptic number.

217532020 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217532020 is an abundant number, since it is smaller than the sum of its proper divisors (244421780).

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

217532020 is a wasteful number, since it uses less digits than its factorization.

217532020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 122307 (or 122305 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 22.

The square root of 217532020 is about 14748.9667434705. The cubic root of 217532020 is about 601.4151964444.

Adding to 217532020 its reverse (20235712), we get a palindrome (237767732).

The spelling of 217532020 in words is "two hundred seventeen million, five hundred thirty-two thousand, twenty".