42752809 has 6 divisors (see below), whose sum is σ = 46992890. Its totient is φ = 38866080.

The previous prime is 42752789. The next prime is 42752851. The reversal of 42752809 is 90825724.

It can be written as a sum of positive squares in only one way, i.e., 27071209 + 15681600 = 5203^2 + 3960^2 .

It is not a de Polignac number, because 42752809 - 2⁷ = 42752681 is a prime.

It is a super-3 number, since 3×42752809³ (a number of 24 digits) contains 333 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 (42752309) 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, 176544 + ... + 176785.

Almost surely, 2^42752809 is an apocalyptic number.

It is an amenable number.

42752809 is a deficient number, since it is larger than the sum of its proper divisors (4240081).

42752809 is a wasteful number, since it uses less digits than its factorization.

42752809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 353351 (or 353340 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 37.

The square root of 42752809 is about 6538.5632213813. The cubic root of 42752809 is about 349.6671911212.

The spelling of 42752809 in words is "forty-two million, seven hundred fifty-two thousand, eight hundred nine".