66670731 has 6 divisors (see below), whose sum is σ = 96302180. Its totient is φ = 44447148.

The previous prime is 66670729. The next prime is 66670759. The reversal of 66670731 is 13707666.

It is not a de Polignac number, because 66670731 - 2¹ = 66670729 is a prime.

It is a super-2 number, since 2×66670731² = 8889972744148722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66670631) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3703921 + ... + 3703938.

Almost surely, 2^66670731 is an apocalyptic number.

66670731 is a deficient number, since it is larger than the sum of its proper divisors (29631449).

66670731 is a wasteful number, since it uses less digits than its factorization.

66670731 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7407865 (or 7407862 counting only the distinct ones).

The product of its (nonzero) digits is 31752, while the sum is 36.

The square root of 66670731 is about 8165.2146940543. The cubic root of 66670731 is about 405.4883729029.

The spelling of 66670731 in words is "sixty-six million, six hundred seventy thousand, seven hundred thirty-one".