21475981792944 has 320 divisors, whose sum is σ = 72739995770880. Its totient is φ = 5936663715840.

The previous prime is 21475981792891. The next prime is 21475981793011. The reversal of 21475981792944 is 44929718957412.

21475981792944 is a `hidden beast` number, since 2 + 1 + 4 + 7 + 598 + 1 + 7 + 9 + 29 + 4 + 4 = 666.

It is a super-2 number, since 2×21475981792944² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 436541212 + ... + 436590404.

It is an arithmetic number, because the mean of its divisors is an integer number (227312486784).

Almost surely, 2^{21475981792944} is an apocalyptic number.

21475981792944 is a gapful number since it is divisible by the number (24) 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 21475981792944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36369997885440).

21475981792944 is an abundant number, since it is smaller than the sum of its proper divisors (51264013977936).

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

21475981792944 is a wasteful number, since it uses less digits than its factorization.

21475981792944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53905 (or 53893 counting only the distinct ones).

The product of its digits is 365783040, while the sum is 72.

The spelling of 21475981792944 in words is "twenty-one trillion, four hundred seventy-five billion, nine hundred eighty-one million, seven hundred ninety-two thousand, nine hundred forty-four".