66897975 has 48 divisors (see below), whose sum is σ = 118920960. Its totient is φ = 33062400.

The previous prime is 66897973. The next prime is 66897977. The reversal of 66897975 is 57979866.

It is an interprime number because it is at equal distance from previous prime (66897973) and next prime (66897977).

It is not a de Polignac number, because 66897975 - 2¹ = 66897973 is a prime.

Its product of digits (5715360) is a multiple of the sum of its prime factors (840).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66897973) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 90156 + ... + 90894.

It is an arithmetic number, because the mean of its divisors is an integer number (2477520).

Almost surely, 2^66897975 is an apocalyptic number.

66897975 is a deficient number, since it is larger than the sum of its proper divisors (52022985).

66897975 is a wasteful number, since it uses less digits than its factorization.

66897975 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 840 (or 835 counting only the distinct ones).

The product of its digits is 5715360, while the sum is 57.

The square root of 66897975 is about 8179.1182287579. The cubic root of 66897975 is about 405.9485463845.

The spelling of 66897975 in words is "sixty-six million, eight hundred ninety-seven thousand, nine hundred seventy-five".