1673721 has 24 divisors (see below), whose sum is σ = 2855424. Its totient is φ = 924480.

The previous prime is 1673719. The next prime is 1673723. The reversal of 1673721 is 1273761.

It is an interprime number because it is at equal distance from previous prime (1673719) and next prime (1673723).

It is not a de Polignac number, because 1673721 - 2¹ = 1673719 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1673723) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1525 + ... + 2381.

It is an arithmetic number, because the mean of its divisors is an integer number (118976).

2^1673721 is an apocalyptic number.

It is an amenable number.

1673721 is a deficient number, since it is larger than the sum of its proper divisors (1181703).

1673721 is a wasteful number, since it uses less digits than its factorization.

1673721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 901 (or 898 counting only the distinct ones).

The product of its digits is 1764, while the sum is 27.

The square root of 1673721 is about 1293.7236953848. The cubic root of 1673721 is about 118.7301514379.

It can be divided in two parts, 16 and 73721, that added together give a palindrome (73737).

The spelling of 1673721 in words is "one million, six hundred seventy-three thousand, seven hundred twenty-one".