42215544391 has 4 divisors (see below), whose sum is σ = 42223857984. Its totient is φ = 42207230800.

The previous prime is 42215544377. The next prime is 42215544401. The reversal of 42215544391 is 19344551224.

42215544391 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 42215544391 - 2²⁷ = 42081326663 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42215544311) 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, 4149175 + ... + 4159336.

It is an arithmetic number, because the mean of its divisors is an integer number (10555964496).

Almost surely, 2^42215544391 is an apocalyptic number.

42215544391 is a deficient number, since it is larger than the sum of its proper divisors (8313593).

42215544391 is an equidigital number, since it uses as much as digits as its factorization.

42215544391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8313592.

The product of its digits is 172800, while the sum is 40.

The spelling of 42215544391 in words is "forty-two billion, two hundred fifteen million, five hundred forty-four thousand, three hundred ninety-one".