42013221520 has 80 divisors (see below), whose sum is σ = 100480287600. Its totient is φ = 16327065600.

The previous prime is 42013221511. The next prime is 42013221521. The reversal of 42013221520 is 2512231024.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 1060414096 + 40952807424 = 32564^2 + 202368^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×42013221520² (a number of 22 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42013221491 and 42013221500.

It is not an unprimeable number, because it can be changed into a prime (42013221521) 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, 763906 + ... + 817054.

It is an arithmetic number, because the mean of its divisors is an integer number (1256003595).

Almost surely, 2^42013221520 is an apocalyptic number.

42013221520 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 42013221520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50240143800).

42013221520 is an abundant number, since it is smaller than the sum of its proper divisors (58467066080).

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

42013221520 is a wasteful number, since it uses less digits than its factorization.

42013221520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53444 (or 53438 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 42013221520 its reverse (2512231024), we get a palindrome (44525452544).

The spelling of 42013221520 in words is "forty-two billion, thirteen million, two hundred twenty-one thousand, five hundred twenty".