66733881 has 8 divisors (see below), whose sum is σ = 89111520. Its totient is φ = 44422752.

The previous prime is 66733861. The next prime is 66733967. The reversal of 66733881 is 18833766.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 66733881 - 2⁹ = 66733369 is a prime.

It is a super-2 number, since 2×66733881² = 8906821746644322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66733811) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14236 + ... + 18333.

It is an arithmetic number, because the mean of its divisors is an integer number (11138940).

Almost surely, 2^66733881 is an apocalyptic number.

It is an amenable number.

66733881 is a deficient number, since it is larger than the sum of its proper divisors (22377639).

66733881 is a wasteful number, since it uses less digits than its factorization.

66733881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33255.

The product of its digits is 145152, while the sum is 42.

The square root of 66733881 is about 8169.0807928432. The cubic root of 66733881 is about 405.6163576514.

The spelling of 66733881 in words is "sixty-six million, seven hundred thirty-three thousand, eight hundred eighty-one".