21534354113440 has 144 divisors (see below), whose sum is σ = 59734115576352. Its totient is φ = 7314204903936.

The previous prime is 21534354113429. The next prime is 21534354113479. The reversal of 21534354113440 is 4431145343512.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a junction number, because it is equal to n+sod(n) for n = 21534354113393 and 21534354113402.

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, 11996302 + ... + 13674061.

It is an arithmetic number, because the mean of its divisors is an integer number (414820247058).

Almost surely, 2^{21534354113440} is an apocalyptic number.

21534354113440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21534354113440 is an abundant number, since it is smaller than the sum of its proper divisors (38199761462912).

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

21534354113440 is a wasteful number, since it uses less digits than its factorization.

21534354113440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 25670499 (or 25670484 counting only the distinct ones).

The product of its (nonzero) digits is 345600, while the sum is 40.

Adding to 21534354113440 its reverse (4431145343512), we get a palindrome (25965499456952).

The spelling of 21534354113440 in words is "twenty-one trillion, five hundred thirty-four billion, three hundred fifty-four million, one hundred thirteen thousand, four hundred forty".