66201572077 has 2 divisors, whose sum is σ = 66201572078. Its totient is φ = 66201572076.

The previous prime is 66201572051. The next prime is 66201572093. The reversal of 66201572077 is 77027510266.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63696169161 + 2505402916 = 252381^2 + 50054^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66201572077 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66201512077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33100786038 + 33100786039.

It is an arithmetic number, because the mean of its divisors is an integer number (33100786039).

Almost surely, 2^66201572077 is an apocalyptic number.

It is an amenable number.

66201572077 is a deficient number, since it is larger than the sum of its proper divisors (1).

66201572077 is an equidigital number, since it uses as much as digits as its factorization.

66201572077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 246960, while the sum is 43.

The spelling of 66201572077 in words is "sixty-six billion, two hundred one million, five hundred seventy-two thousand, seventy-seven".