10661984640 has 384 divisors, whose sum is σ = 38494310400. Its totient is φ = 2819930112.

The previous prime is 10661984623. The next prime is 10661984651. The reversal of 10661984640 is 4648916601.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×10661984640² (a number of 21 digits) contains 22 as substring.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 27837889 + ... + 27838271.

It is an arithmetic number, because the mean of its divisors is an integer number (100245600).

Almost surely, 2^10661984640 is an apocalyptic number.

10661984640 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 10661984640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19247155200).

10661984640 is an abundant number, since it is smaller than the sum of its proper divisors (27832325760).

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

10661984640 is an equidigital number, since it uses as much as digits as its factorization.

10661984640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 596 (or 572 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The spelling of 10661984640 in words is "ten billion, six hundred sixty-one million, nine hundred eighty-four thousand, six hundred forty".