42121618 has 16 divisors (see below), whose sum is σ = 78773184. Its totient is φ = 16410960.

The previous prime is 42121603. The next prime is 42121621. The reversal of 42121618 is 81612124.

It is a junction number, because it is equal to n+sod(n) for n = 42121592 and 42121601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 136605 + ... + 136912.

It is an arithmetic number, because the mean of its divisors is an integer number (4923324).

Almost surely, 2^42121618 is an apocalyptic number.

42121618 is a deficient number, since it is larger than the sum of its proper divisors (36651566).

42121618 is a wasteful number, since it uses less digits than its factorization.

42121618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 273537.

The product of its digits is 768, while the sum is 25.

The square root of 42121618 is about 6490.1169480989. The cubic root of 42121618 is about 347.9378549795.

The spelling of 42121618 in words is "forty-two million, one hundred twenty-one thousand, six hundred eighteen".