21550131440040 has 128 divisors (see below), whose sum is σ = 73999315618560. Its totient is φ = 4918200950784.

The previous prime is 21550131439999. The next prime is 21550131440041. The reversal of 21550131440040 is 4004413105512.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (21550131440041) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19095369 + ... + 20192408.

It is an arithmetic number, because the mean of its divisors is an integer number (578119653270).

Almost surely, 2^{21550131440040} is an apocalyptic number.

21550131440040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21550131440040 is an abundant number, since it is smaller than the sum of its proper divisors (52449184178520).

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

21550131440040 is a wasteful number, since it uses less digits than its factorization.

21550131440040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39288451 (or 39288447 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

Adding to 21550131440040 its reverse (4004413105512), we get a palindrome (25554544545552).

The spelling of 21550131440040 in words is "twenty-one trillion, five hundred fifty billion, one hundred thirty-one million, four hundred forty thousand, forty".