42161261 has 8 divisors (see below), whose sum is σ = 42819840. Its totient is φ = 41506432.

The previous prime is 42161237. The next prime is 42161269. The reversal of 42161261 is 16216124.

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

It is a cyclic number.

It is not a de Polignac number, because 42161261 - 2¹⁴ = 42144877 is a prime.

It is a super-2 number, since 2×42161261² = 3555143858220242, 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 (42161269) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28580 + ... + 30018.

It is an arithmetic number, because the mean of its divisors is an integer number (5352480).

Almost surely, 2^42161261 is an apocalyptic number.

It is an amenable number.

42161261 is a deficient number, since it is larger than the sum of its proper divisors (658579).

42161261 is a wasteful number, since it uses less digits than its factorization.

42161261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1875.

The product of its digits is 576, while the sum is 23.

The square root of 42161261 is about 6493.1703350521. The cubic root of 42161261 is about 348.0469753163.

Adding to 42161261 its reverse (16216124), we get a palindrome (58377385).

The spelling of 42161261 in words is "forty-two million, one hundred sixty-one thousand, two hundred sixty-one".