66047887 has 4 divisors (see below), whose sum is σ = 68178496. Its totient is φ = 63917280.

The previous prime is 66047851. The next prime is 66047893. The reversal of 66047887 is 78874066.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78874066 = 2 ⋅39437033.

It is a cyclic number.

It is not a de Polignac number, because 66047887 - 2¹⁹ = 65523599 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 (66047827) 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, 1065258 + ... + 1065319.

It is an arithmetic number, because the mean of its divisors is an integer number (17044624).

Almost surely, 2^66047887 is an apocalyptic number.

66047887 is a deficient number, since it is larger than the sum of its proper divisors (2130609).

66047887 is a wasteful number, since it uses less digits than its factorization.

66047887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2130608.

The product of its (nonzero) digits is 451584, while the sum is 46.

The square root of 66047887 is about 8126.9851113436. The cubic root of 66047887 is about 404.2217172519.

It can be divided in two parts, 6604788 and 7, that added together give a triangular number (6604795 = T₃₆₃₄).

The spelling of 66047887 in words is "sixty-six million, forty-seven thousand, eight hundred eighty-seven".