1671725378 has 4 divisors (see below), whose sum is σ = 2507588070. Its totient is φ = 835862688.

The previous prime is 1671725351. The next prime is 1671725381. The reversal of 1671725378 is 8735271761.

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

It can be written as a sum of positive squares in only one way, i.e., 1145619409 + 526105969 = 33847^2 + 22937^2 .

It is a Curzon number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 417931343 + ... + 417931346.

Almost surely, 2^1671725378 is an apocalyptic number.

1671725378 is a deficient number, since it is larger than the sum of its proper divisors (835862692).

1671725378 is an equidigital number, since it uses as much as digits as its factorization.

1671725378 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 835862691.

The product of its digits is 493920, while the sum is 47.

The square root of 1671725378 is about 40886.7384123508. The cubic root of 1671725378 is about 1186.8294429985.

The spelling of 1671725378 in words is "one billion, six hundred seventy-one million, seven hundred twenty-five thousand, three hundred seventy-eight".