1678401 has 12 divisors (see below), whose sum is σ = 2514512. Its totient is φ = 1118772.

The previous prime is 1678399. The next prime is 1678409. The reversal of 1678401 is 1048761.

It is a happy number.

It is not a de Polignac number, because 1678401 - 2¹ = 1678399 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1678409) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3211 + ... + 3696.

2^1678401 is an apocalyptic number.

It is an amenable number.

1678401 is a deficient number, since it is larger than the sum of its proper divisors (836111).

1678401 is an frugal number, since it uses more digits than its factorization.

1678401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6922 (or 6910 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 1678401 is about 1295.5311651983. The cubic root of 1678401 is about 118.8407114832.

The spelling of 1678401 in words is "one million, six hundred seventy-eight thousand, four hundred one".