66670531515 has 32 divisors (see below), whose sum is σ = 135457589760. Its totient is φ = 30477956832.

The previous prime is 66670531489. The next prime is 66670531523. The reversal of 66670531515 is 51513507666.

It is not a de Polignac number, because 66670531515 - 2¹⁵ = 66670498747 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 35274469 + ... + 35276358.

It is an arithmetic number, because the mean of its divisors is an integer number (4233049680).

Almost surely, 2^66670531515 is an apocalyptic number.

66670531515 is an abundant number, since it is smaller than the sum of its proper divisors (68787058245).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66670531515 is a wasteful number, since it uses less digits than its factorization.

66670531515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70550848 (or 70550842 counting only the distinct ones).

The product of its (nonzero) digits is 567000, while the sum is 45.

The spelling of 66670531515 in words is "sixty-six billion, six hundred seventy million, five hundred thirty-one thousand, five hundred fifteen".