66491886 has 16 divisors (see below), whose sum is σ = 136578384. Its totient is φ = 21564864.

The previous prime is 66491863. The next prime is 66491899. The reversal of 66491886 is 68819466.

It is a super-3 number, since 3×66491886³ (a number of 24 digits) contains 333 as substring.

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, 149535 + ... + 149978.

It is an arithmetic number, because the mean of its divisors is an integer number (8536149).

Almost surely, 2^66491886 is an apocalyptic number.

66491886 is an abundant number, since it is smaller than the sum of its proper divisors (70086498).

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

66491886 is a wasteful number, since it uses less digits than its factorization.

66491886 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 299555.

The product of its digits is 497664, while the sum is 48.

The square root of 66491886 is about 8154.2556987134. The cubic root of 66491886 is about 405.1254724785.

The spelling of 66491886 in words is "sixty-six million, four hundred ninety-one thousand, eight hundred eighty-six".