1378646543 has 4 divisors (see below), whose sum is σ = 1401247368. Its totient is φ = 1356045720.

The previous prime is 1378646531. The next prime is 1378646561. The reversal of 1378646543 is 3456468731.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3456468731 = 4973 ⋅695047.

It is a cyclic number.

It is not a de Polignac number, because 1378646543 - 2⁴ = 1378646527 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 (1378636543) 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, 11300321 + ... + 11300442.

It is an arithmetic number, because the mean of its divisors is an integer number (350311842).

Almost surely, 2^1378646543 is an apocalyptic number.

1378646543 is a deficient number, since it is larger than the sum of its proper divisors (22600825).

1378646543 is an equidigital number, since it uses as much as digits as its factorization.

1378646543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22600824.

The product of its digits is 1451520, while the sum is 47.

The square root of 1378646543 is about 37130.1298543380. The cubic root of 1378646543 is about 1112.9721883626.

The spelling of 1378646543 in words is "one billion, three hundred seventy-eight million, six hundred forty-six thousand, five hundred forty-three".