66976591 has 4 divisors (see below), whose sum is σ = 73065384. Its totient is φ = 60887800.

The previous prime is 66976561. The next prime is 66976603. The reversal of 66976591 is 19567966.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 66976591 - 2⁹ = 66976079 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66976541) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3044380 + ... + 3044401.

It is an arithmetic number, because the mean of its divisors is an integer number (18266346).

Almost surely, 2^66976591 is an apocalyptic number.

66976591 is a deficient number, since it is larger than the sum of its proper divisors (6088793).

66976591 is a wasteful number, since it uses less digits than its factorization.

66976591 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6088792.

The product of its digits is 612360, while the sum is 49.

The square root of 66976591 is about 8183.9227146888. The cubic root of 66976591 is about 406.1075026543.

The spelling of 66976591 in words is "sixty-six million, nine hundred seventy-six thousand, five hundred ninety-one".