42169381 has 4 divisors (see below), whose sum is σ = 43309132. Its totient is φ = 41029632.

The previous prime is 42169349. The next prime is 42169409. The reversal of 42169381 is 18396124.

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 30980356 + 11189025 = 5566^2 + 3345^2 .

It is a cyclic number.

It is not a de Polignac number, because 42169381 - 2⁵ = 42169349 is a prime.

It is a super-2 number, since 2×42169381² = 3556513387846322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42169301) 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 3 ways as a sum of consecutive naturals, for example, 569820 + ... + 569893.

It is an arithmetic number, because the mean of its divisors is an integer number (10827283).

Almost surely, 2^42169381 is an apocalyptic number.

It is an amenable number.

42169381 is a deficient number, since it is larger than the sum of its proper divisors (1139751).

42169381 is a wasteful number, since it uses less digits than its factorization.

42169381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1139750.

The product of its digits is 10368, while the sum is 34.

The square root of 42169381 is about 6493.7955773184. The cubic root of 42169381 is about 348.0693177855.

The spelling of 42169381 in words is "forty-two million, one hundred sixty-nine thousand, three hundred eighty-one".