66676815 has 24 divisors (see below), whose sum is σ = 119303808. Its totient is φ = 34413120.

The previous prime is 66676811. The next prime is 66676861. The reversal of 66676815 is 51867666.

It is not a de Polignac number, because 66676815 - 2² = 66676811 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66676811) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 22504 + ... + 25293.

It is an arithmetic number, because the mean of its divisors is an integer number (4970992).

Almost surely, 2^66676815 is an apocalyptic number.

66676815 is a deficient number, since it is larger than the sum of its proper divisors (52626993).

66676815 is a wasteful number, since it uses less digits than its factorization.

66676815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47839 (or 47836 counting only the distinct ones).

The product of its digits is 362880, while the sum is 45.

The square root of 66676815 is about 8165.5872415889. The cubic root of 66676815 is about 405.5007067321.

The spelling of 66676815 in words is "sixty-six million, six hundred seventy-six thousand, eight hundred fifteen".