217215340 has 48 divisors (see below), whose sum is σ = 466133472. Its totient is φ = 85003776.

The previous prime is 217215337. The next prime is 217215377. The reversal of 217215340 is 43512712.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 231352 + ... + 232288.

It is an arithmetic number, because the mean of its divisors is an integer number (9711114).

Almost surely, 2^217215340 is an apocalyptic number.

217215340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

217215340 is an abundant number, since it is smaller than the sum of its proper divisors (248918132).

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

217215340 is a wasteful number, since it uses less digits than its factorization.

217215340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1186 (or 1184 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 25.

The square root of 217215340 is about 14738.2271661147. The cubic root of 217215340 is about 601.1232108318.

The spelling of 217215340 in words is "two hundred seventeen million, two hundred fifteen thousand, three hundred forty".