66671015 has 4 divisors (see below), whose sum is σ = 80005224. Its totient is φ = 53336808.

The previous prime is 66670999. The next prime is 66671021. The reversal of 66671015 is 51017666.

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 66671015 - 2⁴ = 66670999 is a prime.

It is a super-2 number, since 2×66671015² = 8890048482260450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6667097 + ... + 6667106.

It is an arithmetic number, because the mean of its divisors is an integer number (20001306).

Almost surely, 2^66671015 is an apocalyptic number.

66671015 is a deficient number, since it is larger than the sum of its proper divisors (13334209).

66671015 is a wasteful number, since it uses less digits than its factorization.

66671015 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13334208.

The product of its (nonzero) digits is 7560, while the sum is 32.

The square root of 66671015 is about 8165.2320848828. The cubic root of 66671015 is about 405.4889486605.

The spelling of 66671015 in words is "sixty-six million, six hundred seventy-one thousand, fifteen".