661082885100 has 864 divisors, whose sum is σ = 2422446953472. Its totient is φ = 155001600000.

The previous prime is 661082885039. The next prime is 661082885107. The reversal of 661082885100 is 1588280166.

661082885100 is a `hidden beast` number, since 6 + 6 + 108 + 28 + 8 + 510 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (661082885107) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 287 ways as a sum of consecutive naturals, for example, 1268872840 + ... + 1268873360.

It is an arithmetic number, because the mean of its divisors is an integer number (2803758048).

Almost surely, 2^661082885100 is an apocalyptic number.

661082885100 is a gapful number since it is divisible by the number (60) 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 661082885100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1211223476736).

661082885100 is an abundant number, since it is smaller than the sum of its proper divisors (1761364068372).

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

661082885100 is a wasteful number, since it uses less digits than its factorization.

661082885100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709 (or 690 counting only the distinct ones).

The product of its (nonzero) digits is 184320, while the sum is 45.

The spelling of 661082885100 in words is "six hundred sixty-one billion, eighty-two million, eight hundred eighty-five thousand, one hundred".