42121445 has 4 divisors (see below), whose sum is σ = 50545740. Its totient is φ = 33697152.

The previous prime is 42121399. The next prime is 42121459. The reversal of 42121445 is 54412124.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 31158724 + 10962721 = 5582^2 + 3311^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42121445 is a prime.

It is a super-2 number, since 2×42121445² = 3548432257776050, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 42121445.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4212140 + ... + 4212149.

It is an arithmetic number, because the mean of its divisors is an integer number (12636435).

Almost surely, 2^42121445 is an apocalyptic number.

It is an amenable number.

42121445 is a deficient number, since it is larger than the sum of its proper divisors (8424295).

42121445 is an equidigital number, since it uses as much as digits as its factorization.

42121445 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8424294.

The product of its digits is 1280, while the sum is 23.

The square root of 42121445 is about 6490.1036201281. The cubic root of 42121445 is about 347.9373786340.

Adding to 42121445 its reverse (54412124), we get a palindrome (96533569).

The spelling of 42121445 in words is "forty-two million, one hundred twenty-one thousand, four hundred forty-five".