21545554343040 has 3072 divisors, whose sum is σ = 98083502899200. Its totient is φ = 4236115968000.

The previous prime is 21545554343009. The next prime is 21545554343063. The reversal of 21545554343040 is 4034345554512.

21545554343040 is a `hidden beast` number, since 2 + 1 + 54 + 5 + 554 + 3 + 4 + 3 + 0 + 40 = 666.

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

It is an unprimeable number.

It is a polite number, since it can be written in 383 ways as a sum of consecutive naturals, for example, 112803949345 + ... + 112803949535.

It is an arithmetic number, because the mean of its divisors is an integer number (31928223600).

Almost surely, 2^{21545554343040} is an apocalyptic number.

21545554343040 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 21545554343040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (49041751449600).

21545554343040 is an abundant number, since it is smaller than the sum of its proper divisors (76537948556160).

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

21545554343040 is a wasteful number, since it uses less digits than its factorization.

21545554343040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 487 (or 472 counting only the distinct ones).

The product of its (nonzero) digits is 2880000, while the sum is 45.

Adding to 21545554343040 its reverse (4034345554512), we get a palindrome (25579899897552).

The spelling of 21545554343040 in words is "twenty-one trillion, five hundred forty-five billion, five hundred fifty-four million, three hundred forty-three thousand, forty".