66550801 has 8 divisors (see below), whose sum is σ = 70636104. Its totient is φ = 62484480.

The previous prime is 66550793. The next prime is 66550807. The reversal of 66550801 is 10805566.

It can be written as a sum of positive squares in 4 ways, for example, as 25603600 + 40947201 = 5060^2 + 6399^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 66550801 - 2³ = 66550793 is a prime.

It is a super-2 number, since 2×66550801² = 8858018227483202, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66550807) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2841 + ... + 11881.

It is an arithmetic number, because the mean of its divisors is an integer number (8829513).

Almost surely, 2^66550801 is an apocalyptic number.

It is an amenable number.

66550801 is a deficient number, since it is larger than the sum of its proper divisors (4085303).

66550801 is a wasteful number, since it uses less digits than its factorization.

66550801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9491.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 66550801 is about 8157.8674296657. The cubic root of 66550801 is about 405.2450906892.

The spelling of 66550801 in words is "sixty-six million, five hundred fifty thousand, eight hundred one".