66503601 has 6 divisors (see below), whose sum is σ = 96060770. Its totient is φ = 44335728.

The previous prime is 66503581. The next prime is 66503621. The reversal of 66503601 is 10630566.

66503601 is a `hidden beast` number, since 6 + 6 + 50 + 3 + 601 = 666.

It is an interprime number because it is at equal distance from previous prime (66503581) and next prime (66503621).

It can be written as a sum of positive squares in only one way, i.e., 46253601 + 20250000 = 6801^2 + 4500^2 .

It is not a de Polignac number, because 66503601 - 2⁶ = 66503537 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66503621) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3694636 + ... + 3694653.

Almost surely, 2^66503601 is an apocalyptic number.

It is an amenable number.

66503601 is a deficient number, since it is larger than the sum of its proper divisors (29557169).

66503601 is a wasteful number, since it uses less digits than its factorization.

66503601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7389295 (or 7389292 counting only the distinct ones).

The product of its (nonzero) digits is 3240, while the sum is 27.

The square root of 66503601 is about 8154.9740036373. The cubic root of 66503601 is about 405.1492636832.

The spelling of 66503601 in words is "sixty-six million, five hundred three thousand, six hundred one".