66515020110 has 432 divisors, whose sum is σ = 228314975616. Its totient is φ = 13372128000.

The previous prime is 66515020109. The next prime is 66515020111. The reversal of 66515020110 is 1102051566.

It is a happy number.

66515020110 is a `hidden beast` number, since 6 + 651 + 5 + 0 + 2 + 0 + 1 + 1 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (66515020109) and next prime (66515020111).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66515020111) by changing a digit.

It is a polite number, since it can be written in 215 ways as a sum of consecutive naturals, for example, 16539900 + ... + 16543920.

It is an arithmetic number, because the mean of its divisors is an integer number (528506888).

Almost surely, 2^66515020110 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 66515020110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (114157487808).

66515020110 is an abundant number, since it is smaller than the sum of its proper divisors (161799955506).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66515020110 is a wasteful number, since it uses less digits than its factorization.

66515020110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4101 (or 4080 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

Adding to 66515020110 its reverse (1102051566), we get a palindrome (67617071676).

The spelling of 66515020110 in words is "sixty-six billion, five hundred fifteen million, twenty thousand, one hundred ten".