42749813 has 2 divisors, whose sum is σ = 42749814. Its totient is φ = 42749812.

The previous prime is 42749797. The next prime is 42749831. The reversal of 42749813 is 31894724.

Together with next prime (42749831) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 41899729 + 850084 = 6473^2 + 922^2 .

It is a cyclic number.

It is not a de Polignac number, because 42749813 - 2⁴ = 42749797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (42749843) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 21374906 + 21374907.

It is an arithmetic number, because the mean of its divisors is an integer number (21374907).

Almost surely, 2^42749813 is an apocalyptic number.

It is an amenable number.

42749813 is a deficient number, since it is larger than the sum of its proper divisors (1).

42749813 is an equidigital number, since it uses as much as digits as its factorization.

42749813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 48384, while the sum is 38.

The square root of 42749813 is about 6538.3341150480. The cubic root of 42749813 is about 349.6590230233.

The spelling of 42749813 in words is "forty-two million, seven hundred forty-nine thousand, eight hundred thirteen".