42506921 has 8 divisors (see below), whose sum is σ = 45786624. Its totient is φ = 39346560.

The previous prime is 42506909. The next prime is 42506923. The reversal of 42506921 is 12960524.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-42506921 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42506923) by changing a digit.

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, 29096 + ... + 30521.

It is an arithmetic number, because the mean of its divisors is an integer number (5723328).

Almost surely, 2^42506921 is an apocalyptic number.

It is an amenable number.

42506921 is a deficient number, since it is larger than the sum of its proper divisors (3279703).

42506921 is a wasteful number, since it uses less digits than its factorization.

42506921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59671.

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 42506921 is about 6519.7332000627. The cubic root of 42506921 is about 348.9955445883.

The spelling of 42506921 in words is "forty-two million, five hundred six thousand, nine hundred twenty-one".