1678397723 has 4 divisors (see below), whose sum is σ = 1678540560. Its totient is φ = 1678254888.

The previous prime is 1678397719. The next prime is 1678397729. The reversal of 1678397723 is 3277938761.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1678397723 - 2² = 1678397719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1678397729) 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, 52040 + ... + 77877.

It is an arithmetic number, because the mean of its divisors is an integer number (419635140).

Almost surely, 2^1678397723 is an apocalyptic number.

1678397723 is a deficient number, since it is larger than the sum of its proper divisors (142837).

1678397723 is a wasteful number, since it uses less digits than its factorization.

1678397723 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142836.

The product of its digits is 2667168, while the sum is 53.

The square root of 1678397723 is about 40968.2526232203. The cubic root of 1678397723 is about 1188.4063413949.

The spelling of 1678397723 in words is "one billion, six hundred seventy-eight million, three hundred ninety-seven thousand, seven hundred twenty-three".