66515601101001 has 64 divisors (see below), whose sum is σ = 100714985978880. Its totient is φ = 38709478229760.

The previous prime is 66515601100999. The next prime is 66515601101009. The reversal of 66515601101001 is 10010110651566.

It is not a de Polignac number, because 66515601101001 - 2¹ = 66515601100999 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66515601101009) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1851598026 + ... + 1851633948.

It is an arithmetic number, because the mean of its divisors is an integer number (1573671655920).

Almost surely, 2^{66515601101001} is an apocalyptic number.

It is an amenable number.

66515601101001 is a deficient number, since it is larger than the sum of its proper divisors (34199384877879).

66515601101001 is a wasteful number, since it uses less digits than its factorization.

66515601101001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40326.

The product of its (nonzero) digits is 5400, while the sum is 33.

Adding to 66515601101001 its reverse (10010110651566), we get a palindrome (76525711752567).

The spelling of 66515601101001 in words is "sixty-six trillion, five hundred fifteen billion, six hundred one million, one hundred one thousand, one".