42521424 has 80 divisors (see below), whose sum is σ = 124009920. Its totient is φ = 12436480.

The previous prime is 42521419. The next prime is 42521443. The reversal of 42521424 is 42412524.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a junction number, because it is equal to n+sod(n) for n = 42521394 and 42521403.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 13924 + ... + 16700.

It is an arithmetic number, because the mean of its divisors is an integer number (1550124).

Almost surely, 2^42521424 is an apocalyptic number.

42521424 is a gapful number since it is divisible by the number (44) 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 42521424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62004960).

42521424 is an abundant number, since it is smaller than the sum of its proper divisors (81488496).

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

42521424 is a wasteful number, since it uses less digits than its factorization.

42521424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2828 (or 2822 counting only the distinct ones).

The product of its digits is 2560, while the sum is 24.

The square root of 42521424 is about 6520.8453439719. The cubic root of 42521424 is about 349.0352315125.

Adding to 42521424 its reverse (42412524), we get a palindrome (84933948).

Subtracting from 42521424 its reverse (42412524), we obtain a square (108900 = 330²).

The spelling of 42521424 in words is "forty-two million, five hundred twenty-one thousand, four hundred twenty-four".