66897701 has 4 divisors (see below), whose sum is σ = 72043692. Its totient is φ = 61751712.

The previous prime is 66897697. The next prime is 66897707. The reversal of 66897701 is 10779866.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 41152225 + 25745476 = 6415^2 + 5074^2 .

It is a cyclic number.

It is not a de Polignac number, because 66897701 - 2² = 66897697 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66897707) 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, 2572976 + ... + 2573001.

It is an arithmetic number, because the mean of its divisors is an integer number (18010923).

Almost surely, 2^66897701 is an apocalyptic number.

It is an amenable number.

66897701 is a deficient number, since it is larger than the sum of its proper divisors (5145991).

66897701 is a wasteful number, since it uses less digits than its factorization.

66897701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5145990.

The product of its (nonzero) digits is 127008, while the sum is 44.

The square root of 66897701 is about 8179.1014787689. The cubic root of 66897701 is about 405.9479921572.

The spelling of 66897701 in words is "sixty-six million, eight hundred ninety-seven thousand, seven hundred one".