1001664566100 has 864 divisors, whose sum is σ = 3596089835520. Its totient is φ = 231071616000.

The previous prime is 1001664566087. The next prime is 1001664566101. The reversal of 1001664566100 is 16654661001.

It is a happy number.

1001664566100 is a `hidden beast` number, since 1 + 0 + 0 + 1 + 6 + 645 + 6 + 6 + 1 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001664566101) by changing a digit.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 5244317005 + ... + 5244317195.

Almost surely, 2^{1001664566100} is an apocalyptic number.

1001664566100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001664566100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1798044917760).

1001664566100 is an abundant number, since it is smaller than the sum of its proper divisors (2594425269420).

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

1001664566100 is a wasteful number, since it uses less digits than its factorization.

1001664566100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 501 (or 491 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The spelling of 1001664566100 in words is "one trillion, one billion, six hundred sixty-four million, five hundred sixty-six thousand, one hundred".