781342939 has 6 divisors (see below), whose sum is σ = 846069756. Its totient is φ = 721239480.

The previous prime is 781342931. The next prime is 781342957. The reversal of 781342939 is 939243187.

It is not a de Polignac number, because 781342939 - 2³ = 781342931 is a prime.

It is a super-2 number, since 2×781342939² = 1220993576650315442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (781342931) 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, 2311497 + ... + 2311834.

It is an arithmetic number, because the mean of its divisors is an integer number (141011626).

Almost surely, 2^781342939 is an apocalyptic number.

781342939 is a deficient number, since it is larger than the sum of its proper divisors (64726817).

781342939 is a wasteful number, since it uses less digits than its factorization.

781342939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4623357 (or 4623344 counting only the distinct ones).

The product of its digits is 326592, while the sum is 46.

The square root of 781342939 is about 27952.5122126796. The cubic root of 781342939 is about 921.0443948337.

The spelling of 781342939 in words is "seven hundred eighty-one million, three hundred forty-two thousand, nine hundred thirty-nine".