66631404 has 96 divisors (see below), whose sum is σ = 189665280. Its totient is φ = 17782848.

The previous prime is 66631403. The next prime is 66631427. The reversal of 66631404 is 40413666.

It is a super-2 number, since 2×66631404² = 8879487998022432, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66631403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 132217 + ... + 132719.

It is an arithmetic number, because the mean of its divisors is an integer number (1975680).

Almost surely, 2^66631404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66631404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94832640).

66631404 is an abundant number, since it is smaller than the sum of its proper divisors (123033876).

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

66631404 is a wasteful number, since it uses less digits than its factorization.

66631404 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 619 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 30.

The square root of 66631404 is about 8162.8061351474. The cubic root of 66631404 is about 405.4086288758.

The spelling of 66631404 in words is "sixty-six million, six hundred thirty-one thousand, four hundred four".