66506501 has 16 divisors (see below), whose sum is σ = 73602048. Its totient is φ = 59875200.

The previous prime is 66506497. The next prime is 66506507. The reversal of 66506501 is 10560566.

It is a cyclic number.

It is not a de Polignac number, because 66506501 - 2² = 66506497 is a prime.

It is a super-2 number, since 2×66506501² = 8846229350526002, which contains 22 as substring.

It is a Smith number, since the sum of its digits (29) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66506507) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25121 + ... + 27641.

It is an arithmetic number, because the mean of its divisors is an integer number (4600128).

Almost surely, 2^66506501 is an apocalyptic number.

It is an amenable number.

66506501 is a deficient number, since it is larger than the sum of its proper divisors (7095547).

66506501 is a wasteful number, since it uses less digits than its factorization.

66506501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2612.

The product of its (nonzero) digits is 5400, while the sum is 29.

The square root of 66506501 is about 8155.1518072934. The cubic root of 66506501 is about 405.1551526665.

The spelling of 66506501 in words is "sixty-six million, five hundred six thousand, five hundred one".