21552505442040 has 64 divisors (see below), whose sum is σ = 66234528934560. Its totient is φ = 5607155886080.

The previous prime is 21552505442033. The next prime is 21552505442047. The reversal of 21552505442040 is 4024450525512.

It is an interprime number because it is at equal distance from previous prime (21552505442033) and next prime (21552505442047).

It is a self number, because there is not a number n which added to its sum of digits gives 21552505442040.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21552505442047) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2190290349 + ... + 2190300188.

Almost surely, 2^{21552505442040} is an apocalyptic number.

21552505442040 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21552505442040 is an abundant number, since it is smaller than the sum of its proper divisors (44682023492520).

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

21552505442040 is a wasteful number, since it uses less digits than its factorization.

21552505442040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4380590592 (or 4380590588 counting only the distinct ones).

The product of its (nonzero) digits is 320000, while the sum is 39.

Adding to 21552505442040 its reverse (4024450525512), we get a palindrome (25576955967552).

The spelling of 21552505442040 in words is "twenty-one trillion, five hundred fifty-two billion, five hundred five million, four hundred forty-two thousand, forty".