66561551006 has 8 divisors (see below), whose sum is σ = 102540767880. Its totient is φ = 32381295048.

The previous prime is 66561551003. The next prime is 66561551039. The reversal of 66561551006 is 60015516566.

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

It is a super-2 number, since 2×66561551006² (a number of 22 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66561551003) 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, 449740136 + ... + 449740283.

It is an arithmetic number, because the mean of its divisors is an integer number (12817595985).

Almost surely, 2^66561551006 is an apocalyptic number.

66561551006 is a deficient number, since it is larger than the sum of its proper divisors (35979216874).

66561551006 is a wasteful number, since it uses less digits than its factorization.

66561551006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 899480458.

The product of its (nonzero) digits is 162000, while the sum is 41.

The spelling of 66561551006 in words is "sixty-six billion, five hundred sixty-one million, five hundred fifty-one thousand, six".