399681349543 has 4 divisors (see below), whose sum is σ = 456778685200. Its totient is φ = 342584013888.

The previous prime is 399681349537. The next prime is 399681349549. The reversal of 399681349543 is 345943186993.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 345943186993 = 317 ⋅1091303429.

It is an interprime number because it is at equal distance from previous prime (399681349537) and next prime (399681349549).

It is a cyclic number.

It is not a de Polignac number, because 399681349543 - 2⁹ = 399681349031 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (399681349549) 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, 28548667818 + ... + 28548667831.

It is an arithmetic number, because the mean of its divisors is an integer number (114194671300).

Almost surely, 2^399681349543 is an apocalyptic number.

399681349543 is a deficient number, since it is larger than the sum of its proper divisors (57097335657).

399681349543 is an equidigital number, since it uses as much as digits as its factorization.

399681349543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57097335656.

The product of its digits is 75582720, while the sum is 64.

The spelling of 399681349543 in words is "three hundred ninety-nine billion, six hundred eighty-one million, three hundred forty-nine thousand, five hundred forty-three".