42778729 has 8 divisors (see below), whose sum is σ = 50467328. Its totient is φ = 35484480.

The previous prime is 42778699. The next prime is 42778739. The reversal of 42778729 is 92787724.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 42778729 - 2⁹ = 42778217 is a prime.

It is a super-3 number, since 3×42778729³ (a number of 24 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42778739) 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, 98352 + ... + 98785.

It is an arithmetic number, because the mean of its divisors is an integer number (6308416).

Almost surely, 2^42778729 is an apocalyptic number.

It is an amenable number.

42778729 is a deficient number, since it is larger than the sum of its proper divisors (7688599).

42778729 is a wasteful number, since it uses less digits than its factorization.

42778729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197175.

The product of its digits is 395136, while the sum is 46.

The square root of 42778729 is about 6540.5450078721. The cubic root of 42778729 is about 349.7378417816.

The spelling of 42778729 in words is "forty-two million, seven hundred seventy-eight thousand, seven hundred twenty-nine".