42102505 has 8 divisors (see below), whose sum is σ = 51351624. Its totient is φ = 33129600.

The previous prime is 42102493. The next prime is 42102509. The reversal of 42102505 is 50520124.

42102505 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 5184729 + 36917776 = 2277^2 + 6076^2 .

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

It is not a de Polignac number, because 42102505 - 2⁹ = 42101993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42102509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 68716 + ... + 69325.

It is an arithmetic number, because the mean of its divisors is an integer number (6418953).

Almost surely, 2^42102505 is an apocalyptic number.

It is an amenable number.

42102505 is a deficient number, since it is larger than the sum of its proper divisors (9249119).

42102505 is a wasteful number, since it uses less digits than its factorization.

42102505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138107.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 42102505 is about 6488.6443114105. The cubic root of 42102505 is about 347.8852205474.

Adding to 42102505 its reverse (50520124), we get a palindrome (92622629).

The spelling of 42102505 in words is "forty-two million, one hundred two thousand, five hundred five".