42781123 has 24 divisors (see below), whose sum is σ = 54813024. Its totient is φ = 32672640.

The previous prime is 42781099. The next prime is 42781159. The reversal of 42781123 is 32118724.

It is not a de Polignac number, because 42781123 - 2⁵ = 42781091 is a prime.

It is a super-2 number, since 2×42781123² = 3660448970282258, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 42781091 and 42781100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42781183) 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, 44415 + ... + 45367.

It is an arithmetic number, because the mean of its divisors is an integer number (2283876).

Almost surely, 2^42781123 is an apocalyptic number.

42781123 is a deficient number, since it is larger than the sum of its proper divisors (12031901).

42781123 is a wasteful number, since it uses less digits than its factorization.

42781123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1035 (or 1024 counting only the distinct ones).

The product of its digits is 2688, while the sum is 28.

The square root of 42781123 is about 6540.7280175834. The cubic root of 42781123 is about 349.7443657153.

Adding to 42781123 its reverse (32118724), we get a palindrome (74899847).

The spelling of 42781123 in words is "forty-two million, seven hundred eighty-one thousand, one hundred twenty-three".