66541697 has 4 divisors (see below), whose sum is σ = 67478976. Its totient is φ = 65604420.

The previous prime is 66541693. The next prime is 66541703. The reversal of 66541697 is 79614566.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 79614566 = 2 ⋅39807283.

It is a cyclic number.

It is not a de Polignac number, because 66541697 - 2² = 66541693 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66541693) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 468533 + ... + 468674.

It is an arithmetic number, because the mean of its divisors is an integer number (16869744).

Almost surely, 2^66541697 is an apocalyptic number.

It is an amenable number.

66541697 is a deficient number, since it is larger than the sum of its proper divisors (937279).

66541697 is an equidigital number, since it uses as much as digits as its factorization.

66541697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 937278.

The product of its digits is 272160, while the sum is 44.

The square root of 66541697 is about 8157.3094216169. The cubic root of 66541697 is about 405.2266109740.

The spelling of 66541697 in words is "sixty-six million, five hundred forty-one thousand, six hundred ninety-seven".