42121255440 has 240 divisors, whose sum is σ = 145853075520. Its totient is φ = 9972587520.

The previous prime is 42121255417. The next prime is 42121255469. The reversal of 42121255440 is 4455212124.

42121255440 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (240).

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

It is a junction number, because it is equal to n+sod(n) for n = 42121255398 and 42121255407.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 4877046 + ... + 4885674.

It is an arithmetic number, because the mean of its divisors is an integer number (607721148).

Almost surely, 2^42121255440 is an apocalyptic number.

42121255440 is a gapful number since it is divisible by the number (40) 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 42121255440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (72926537760).

42121255440 is an abundant number, since it is smaller than the sum of its proper divisors (103731820080).

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

42121255440 is a wasteful number, since it uses less digits than its factorization.

42121255440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8742 (or 8693 counting only the distinct ones).

The product of its (nonzero) digits is 12800, while the sum is 30.

Adding to 42121255440 its reverse (4455212124), we get a palindrome (46576467564).

The spelling of 42121255440 in words is "forty-two billion, one hundred twenty-one million, two hundred fifty-five thousand, four hundred forty".