42230781 has 8 divisors (see below), whose sum is σ = 62564160. Its totient is φ = 28153836.

The previous prime is 42230777. The next prime is 42230789. The reversal of 42230781 is 18703224.

It is not a de Polignac number, because 42230781 - 2² = 42230777 is a prime.

It is a super-2 number, since 2×42230781² = 3566877727739922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 1564103 = 42230781 / (4 + 2 + 2 + 3 + 0 + 7 + 8 + 1).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42230789) 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, 782025 + ... + 782078.

It is an arithmetic number, because the mean of its divisors is an integer number (7820520).

Almost surely, 2^42230781 is an apocalyptic number.

It is an amenable number.

42230781 is a deficient number, since it is larger than the sum of its proper divisors (20333379).

42230781 is a wasteful number, since it uses less digits than its factorization.

42230781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1564112 (or 1564106 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 42230781 is about 6498.5214472217. The cubic root of 42230781 is about 348.2381693035.

The spelling of 42230781 in words is "forty-two million, two hundred thirty thousand, seven hundred eighty-one".