42345981 has 6 divisors (see below), whose sum is σ = 61166430. Its totient is φ = 28230648.

The previous prime is 42345977. The next prime is 42345983. The reversal of 42345981 is 18954324.

It can be written as a sum of positive squares in only one way, i.e., 40068900 + 2277081 = 6330^2 + 1509^2 .

It is not a de Polignac number, because 42345981 - 2² = 42345977 is a prime.

It is a super-2 number, since 2×42345981² = 3586364213704722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (42345983) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2352546 + ... + 2352563.

It is an arithmetic number, because the mean of its divisors is an integer number (10194405).

Almost surely, 2^42345981 is an apocalyptic number.

It is an amenable number.

42345981 is a deficient number, since it is larger than the sum of its proper divisors (18820449).

42345981 is a wasteful number, since it uses less digits than its factorization.

42345981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4705115 (or 4705112 counting only the distinct ones).

The product of its digits is 34560, while the sum is 36.

The square root of 42345981 is about 6507.3789654515. The cubic root of 42345981 is about 348.5545310768.

The spelling of 42345981 in words is "forty-two million, three hundred forty-five thousand, nine hundred eighty-one".