42809621 has 16 divisors (see below), whose sum is σ = 46759680. Its totient is φ = 39037440.

The previous prime is 42809593. The next prime is 42809651. The reversal of 42809621 is 12690824.

It is a de Polignac number, because none of the positive numbers 2^k-42809621 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42809651) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104465 + ... + 104873.

It is an arithmetic number, because the mean of its divisors is an integer number (2922480).

Almost surely, 2^42809621 is an apocalyptic number.

It is an amenable number.

42809621 is a deficient number, since it is larger than the sum of its proper divisors (3950059).

42809621 is a wasteful number, since it uses less digits than its factorization.

42809621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 604.

The product of its (nonzero) digits is 6912, while the sum is 32.

The square root of 42809621 is about 6542.9061585812. The cubic root of 42809621 is about 349.8220074564.

The spelling of 42809621 in words is "forty-two million, eight hundred nine thousand, six hundred twenty-one".