10661265961920 has 672 divisors, whose sum is σ = 43536000807936. Its totient is φ = 2343927398400.

The previous prime is 10661265961877. The next prime is 10661265961933. The reversal of 10661265961920 is 2916956216601.

10661265961920 is a `hidden beast` number, since 1 + 0 + 6 + 6 + 1 + 26 + 596 + 1 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (672).

It is a super-2 number, since 2×10661265961920² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 58594927 + ... + 58776593.

It is an arithmetic number, because the mean of its divisors is an integer number (64785715488).

Almost surely, 2^{10661265961920} is an apocalyptic number.

10661265961920 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 10661265961920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21768000403968).

10661265961920 is an abundant number, since it is smaller than the sum of its proper divisors (32874734846016).

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

10661265961920 is a wasteful number, since it uses less digits than its factorization.

10661265961920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181809 (or 181796 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 10661265961920 in words is "ten trillion, six hundred sixty-one billion, two hundred sixty-five million, nine hundred sixty-one thousand, nine hundred twenty".