66885231087 has 16 divisors (see below), whose sum is σ = 99217450080. Its totient is φ = 44532455616.

The previous prime is 66885231079. The next prime is 66885231097. The reversal of 66885231087 is 78013258866.

66885231087 is a `hidden beast` number, since 6 + 6 + 8 + 8 + 523 + 108 + 7 = 666.

It is not a de Polignac number, because 66885231087 - 2³ = 66885231079 is a prime.

It is a super-2 number, since 2×66885231087² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66885231067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1581478 + ... + 1623219.

It is an arithmetic number, because the mean of its divisors is an integer number (6201090630).

Almost surely, 2^66885231087 is an apocalyptic number.

66885231087 is a deficient number, since it is larger than the sum of its proper divisors (32332218993).

66885231087 is a wasteful number, since it uses less digits than its factorization.

66885231087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3205479 (or 3205473 counting only the distinct ones).

The product of its (nonzero) digits is 3870720, while the sum is 54.

The spelling of 66885231087 in words is "sixty-six billion, eight hundred eighty-five million, two hundred thirty-one thousand, eighty-seven".