217966812 has 48 divisors (see below), whose sum is σ = 589935360. Its totient is φ = 61345152.

The previous prime is 217966807. The next prime is 217966817. The reversal of 217966812 is 218669712.

It is an interprime number because it is at equal distance from previous prime (217966807) and next prime (217966817).

It is a super-2 number, since 2×217966812² = 95019062266886688, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (217966817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13737 + ... + 24992.

It is an arithmetic number, because the mean of its divisors is an integer number (12290320).

Almost surely, 2^217966812 is an apocalyptic number.

It is an amenable number.

217966812 is an abundant number, since it is smaller than the sum of its proper divisors (371968548).

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

217966812 is a wasteful number, since it uses less digits than its factorization.

217966812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38810 (or 38808 counting only the distinct ones).

The product of its digits is 72576, while the sum is 42.

The square root of 217966812 is about 14763.6991299606. The cubic root of 217966812 is about 601.8156225384.

The spelling of 217966812 in words is "two hundred seventeen million, nine hundred sixty-six thousand, eight hundred twelve".