42157645 has 4 divisors (see below), whose sum is σ = 50589180. Its totient is φ = 33726112.

The previous prime is 42157607. The next prime is 42157651. The reversal of 42157645 is 54675124.

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

It can be written as a sum of positive squares in 2 ways, for example, as 12411529 + 29746116 = 3523^2 + 5454^2 .

It is a cyclic number.

It is not a de Polignac number, because 42157645 - 2¹⁷ = 42026573 is a prime.

It is a super-3 number, since 3×42157645³ (a number of 24 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 42157645.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 4215760 + ... + 4215769.

It is an arithmetic number, because the mean of its divisors is an integer number (12647295).

Almost surely, 2^42157645 is an apocalyptic number.

It is an amenable number.

42157645 is a deficient number, since it is larger than the sum of its proper divisors (8431535).

42157645 is an equidigital number, since it uses as much as digits as its factorization.

42157645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8431534.

The product of its digits is 33600, while the sum is 34.

The square root of 42157645 is about 6492.8918826668. The cubic root of 42157645 is about 348.0370248403.

The spelling of 42157645 in words is "forty-two million, one hundred fifty-seven thousand, six hundred forty-five".