1667942447 has 4 divisors (see below), whose sum is σ = 1668096696. Its totient is φ = 1667788200.

The previous prime is 1667942407. The next prime is 1667942501. The reversal of 1667942447 is 7442497661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 7442497661 = 271 ⋅27463091.

It is a cyclic number.

It is not a de Polignac number, because 1667942447 - 2⁸ = 1667942191 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1667942395 and 1667942404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1667942407) 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, 59573 + ... + 82974.

It is an arithmetic number, because the mean of its divisors is an integer number (417024174).

Almost surely, 2^1667942447 is an apocalyptic number.

1667942447 is a deficient number, since it is larger than the sum of its proper divisors (154249).

1667942447 is a wasteful number, since it uses less digits than its factorization.

1667942447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 154248.

The product of its digits is 2032128, while the sum is 50.

The square root of 1667942447 is about 40840.4511116124. The cubic root of 1667942447 is about 1185.9335453078.

The spelling of 1667942447 in words is "one billion, six hundred sixty-seven million, nine hundred forty-two thousand, four hundred forty-seven".