66491431 has 8 divisors (see below), whose sum is σ = 70686000. Its totient is φ = 62366400.

The previous prime is 66491419. The next prime is 66491441. The reversal of 66491431 is 13419466.

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

It is a cyclic number.

It is not a de Polignac number, because 66491431 - 2⁷ = 66491303 is a prime.

It is a super-2 number, since 2×66491431² = 8842220792855522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66491441) 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, 15406 + ... + 19243.

It is an arithmetic number, because the mean of its divisors is an integer number (8835750).

Almost surely, 2^66491431 is an apocalyptic number.

66491431 is a deficient number, since it is larger than the sum of its proper divisors (4194569).

66491431 is a wasteful number, since it uses less digits than its factorization.

66491431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34769.

The product of its digits is 15552, while the sum is 34.

The square root of 66491431 is about 8154.2277991236. The cubic root of 66491431 is about 405.1245483933.

The spelling of 66491431 in words is "sixty-six million, four hundred ninety-one thousand, four hundred thirty-one".