66195812 has 24 divisors (see below), whose sum is σ = 121886520. Its totient is φ = 31415040.

The previous prime is 66195803. The next prime is 66195821. The reversal of 66195812 is 21859166.

It is an interprime number because it is at equal distance from previous prime (66195803) and next prime (66195821).

It can be written as a sum of positive squares in 4 ways, for example, as 2579236 + 63616576 = 1606^2 + 7976^2 .

It is a Smith number, since the sum of its digits (38) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 614 + ... + 11522.

It is an arithmetic number, because the mean of its divisors is an integer number (5078605).

Almost surely, 2^66195812 is an apocalyptic number.

It is an amenable number.

66195812 is a deficient number, since it is larger than the sum of its proper divisors (55690708).

66195812 is a wasteful number, since it uses less digits than its factorization.

66195812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10991 (or 10989 counting only the distinct ones).

The product of its digits is 25920, while the sum is 38.

The square root of 66195812 is about 8136.0808747209. The cubic root of 66195812 is about 404.5232656983.

The spelling of 66195812 in words is "sixty-six million, one hundred ninety-five thousand, eight hundred twelve".