20961094440 has 512 divisors, whose sum is σ = 77605516800. Its totient is φ = 4459069440.

The previous prime is 20961094423. The next prime is 20961094543. The reversal of 20961094440 is 4449016902.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 36327432 + ... + 36328008.

It is an arithmetic number, because the mean of its divisors is an integer number (151573275).

Almost surely, 2^20961094440 is an apocalyptic number.

20961094440 is a gapful number since it is divisible by the number (20) 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 20961094440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38802758400).

20961094440 is an abundant number, since it is smaller than the sum of its proper divisors (56644422360).

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

20961094440 is a wasteful number, since it uses less digits than its factorization.

20961094440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717 (or 713 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 39.

The spelling of 20961094440 in words is "twenty billion, nine hundred sixty-one million, ninety-four thousand, four hundred forty".