42121404 has 96 divisors (see below), whose sum is σ = 123872000. Its totient is φ = 12270528.

The previous prime is 42121399. The next prime is 42121459. The reversal of 42121404 is 40412124.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25887 + ... + 27465.

Almost surely, 2^42121404 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42121404, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (61936000).

42121404 is an abundant number, since it is smaller than the sum of its proper divisors (81750596).

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

42121404 is a wasteful number, since it uses less digits than its factorization.

42121404 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1624 (or 1616 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 42121404 is about 6490.1004614721. The cubic root of 42121404 is about 347.9372657427.

Adding to 42121404 its reverse (40412124), we get a palindrome (82533528).

The spelling of 42121404 in words is "forty-two million, one hundred twenty-one thousand, four hundred four".