42392809 has 4 divisors (see below), whose sum is σ = 43854660. Its totient is φ = 40930960.

The previous prime is 42392807. The next prime is 42392813. The reversal of 42392809 is 90829324.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 29811600 + 12581209 = 5460^2 + 3547^2 .

It is a cyclic number.

It is not a de Polignac number, because 42392809 - 2¹ = 42392807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42392803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 730882 + ... + 730939.

It is an arithmetic number, because the mean of its divisors is an integer number (10963665).

Almost surely, 2^42392809 is an apocalyptic number.

It is an amenable number.

42392809 is a deficient number, since it is larger than the sum of its proper divisors (1461851).

42392809 is a wasteful number, since it uses less digits than its factorization.

42392809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1461850.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 42392809 is about 6510.9760405027. The cubic root of 42392809 is about 348.6829659233.

The spelling of 42392809 in words is "forty-two million, three hundred ninety-two thousand, eight hundred nine".