66671731 has 8 divisors (see below), whose sum is σ = 78654464. Its totient is φ = 55303560.

The previous prime is 66671729. The next prime is 66671771. The reversal of 66671731 is 13717666.

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 66671731 - 2¹ = 66671729 is a prime.

It is a super-2 number, since 2×66671731² = 8890239429072722, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (66671701) 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, 153405 + ... + 153838.

It is an arithmetic number, because the mean of its divisors is an integer number (9831808).

Almost surely, 2^66671731 is an apocalyptic number.

66671731 is a deficient number, since it is larger than the sum of its proper divisors (11982733).

66671731 is a wasteful number, since it uses less digits than its factorization.

66671731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 307281.

The product of its digits is 31752, while the sum is 37.

The square root of 66671731 is about 8165.2759292017. The cubic root of 66671731 is about 405.4904002110.

The spelling of 66671731 in words is "sixty-six million, six hundred seventy-one thousand, seven hundred thirty-one".