66217612 has 12 divisors (see below), whose sum is σ = 119619136. Its totient is φ = 32040720.

The previous prime is 66217589. The next prime is 66217633. The reversal of 66217612 is 21671266.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266883 + ... + 267130.

Almost surely, 2^66217612 is an apocalyptic number.

66217612 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

66217612 is a deficient number, since it is larger than the sum of its proper divisors (53401524).

66217612 is a wasteful number, since it uses less digits than its factorization.

66217612 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 534048 (or 534046 counting only the distinct ones).

The product of its digits is 6048, while the sum is 31.

The square root of 66217612 is about 8137.4204758019. The cubic root of 66217612 is about 404.5676674968.

Adding to 66217612 its reverse (21671266), we get a palindrome (87888878).

The spelling of 66217612 in words is "sixty-six million, two hundred seventeen thousand, six hundred twelve".