21403564773600 has 144 divisors (see below), whose sum is σ = 69701969882160. Its totient is φ = 5704883712000.

The previous prime is 21403564773581. The next prime is 21403564773629. The reversal of 21403564773600 is 637746530412.

It is a super-2 number, since 2×21403564773600² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 21403564773600.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2879050 + ... + 7148150.

It is an arithmetic number, because the mean of its divisors is an integer number (484041457515).

Almost surely, 2^{21403564773600} is an apocalyptic number.

21403564773600 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 21403564773600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34850984941080).

21403564773600 is an abundant number, since it is smaller than the sum of its proper divisors (48298405108560).

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

21403564773600 is a wasteful number, since it uses less digits than its factorization.

21403564773600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4271213 (or 4271200 counting only the distinct ones).

The product of its (nonzero) digits is 2540160, while the sum is 48.

The spelling of 21403564773600 in words is "twenty-one trillion, four hundred three billion, five hundred sixty-four million, seven hundred seventy-three thousand, six hundred".