42405621 has 4 divisors (see below), whose sum is σ = 56540832. Its totient is φ = 28270412.

The previous prime is 42405619. The next prime is 42405647. The reversal of 42405621 is 12650424.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 42405621 - 2¹ = 42405619 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 42405591 and 42405600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42405691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7067601 + ... + 7067606.

It is an arithmetic number, because the mean of its divisors is an integer number (14135208).

Almost surely, 2^42405621 is an apocalyptic number.

It is an amenable number.

42405621 is a deficient number, since it is larger than the sum of its proper divisors (14135211).

42405621 is a wasteful number, since it uses less digits than its factorization.

42405621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14135210.

The product of its (nonzero) digits is 1920, while the sum is 24.

The square root of 42405621 is about 6511.9598432423. The cubic root of 42405621 is about 348.7180888313.

The spelling of 42405621 in words is "forty-two million, four hundred five thousand, six hundred twenty-one".