42121530 has 96 divisors (see below), whose sum is σ = 120676608. Its totient is φ = 10108800.

The previous prime is 42121501. The next prime is 42121549. The reversal of 42121530 is 3512124.

42121530 is a `hidden beast` number, since 421 + 215 + 30 = 666.

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

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, 155295 + ... + 155565.

It is an arithmetic number, because the mean of its divisors is an integer number (1257048).

Almost surely, 2^42121530 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 42121530, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (60338304).

42121530 is an abundant number, since it is smaller than the sum of its proper divisors (78555078).

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

42121530 is a wasteful number, since it uses less digits than its factorization.

42121530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 452 (or 449 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 42121530 is about 6490.1101685565. The cubic root of 42121530 is about 347.9376126767.

Adding to 42121530 its reverse (3512124), we get a palindrome (45633654).

The spelling of 42121530 in words is "forty-two million, one hundred twenty-one thousand, five hundred thirty".