42542709 has 24 divisors (see below), whose sum is σ = 64714272. Its totient is φ = 24652320.

The previous prime is 42542701. The next prime is 42542713. The reversal of 42542709 is 90724524.

It is not a de Polignac number, because 42542709 - 2³ = 42542701 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a self number, because there is not a number n which added to its sum of digits gives 42542709.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42542701) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16239 + ... + 18675.

It is an arithmetic number, because the mean of its divisors is an integer number (2696428).

Almost surely, 2^42542709 is an apocalyptic number.

It is an amenable number.

42542709 is a deficient number, since it is larger than the sum of its proper divisors (22171563).

42542709 is a wasteful number, since it uses less digits than its factorization.

42542709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2497 (or 2474 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 33.

The square root of 42542709 is about 6522.4772134520. The cubic root of 42542709 is about 349.0934607918.

It can be divided in two parts, 425 and 42709, that added together give a palindrome (43134).

The spelling of 42542709 in words is "forty-two million, five hundred forty-two thousand, seven hundred nine".