42891739409 has 4 divisors (see below), whose sum is σ = 43594882740. Its totient is φ = 42188596080.

The previous prime is 42891739399. The next prime is 42891739477. The reversal of 42891739409 is 90493719824.

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 1480710400 + 41411029009 = 38480^2 + 203497^2 .

It is a cyclic number.

It is not a de Polignac number, because 42891739409 - 2³² = 38596772113 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (42891739309) 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, 351571574 + ... + 351571695.

It is an arithmetic number, because the mean of its divisors is an integer number (10898720685).

Almost surely, 2^42891739409 is an apocalyptic number.

It is an amenable number.

42891739409 is a deficient number, since it is larger than the sum of its proper divisors (703143331).

42891739409 is an equidigital number, since it uses as much as digits as its factorization.

42891739409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703143330.

The product of its (nonzero) digits is 3919104, while the sum is 56.

The spelling of 42891739409 in words is "forty-two billion, eight hundred ninety-one million, seven hundred thirty-nine thousand, four hundred nine".