1386640973 has 4 divisors (see below), whose sum is σ = 1386943008. Its totient is φ = 1386338940.

The previous prime is 1386640963. The next prime is 1386640987. The reversal of 1386640973 is 3790466831.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 3790466831 = 4861 ⋅779771.

It is a cyclic number.

It is not a de Polignac number, because 1386640973 - 2¹⁰ = 1386639949 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 (1386640933) 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, 144023 + ... + 153348.

It is an arithmetic number, because the mean of its divisors is an integer number (346735752).

Almost surely, 2^1386640973 is an apocalyptic number.

It is an amenable number.

1386640973 is a deficient number, since it is larger than the sum of its proper divisors (302035).

1386640973 is an equidigital number, since it uses as much as digits as its factorization.

1386640973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 302034.

The product of its (nonzero) digits is 653184, while the sum is 47.

The square root of 1386640973 is about 37237.6284556361. The cubic root of 1386640973 is about 1115.1193268500.

The spelling of 1386640973 in words is "one billion, three hundred eighty-six million, six hundred forty thousand, nine hundred seventy-three".