1721967 has 16 divisors (see below), whose sum is σ = 2513280. Its totient is φ = 1042272.

The previous prime is 1721927. The next prime is 1721983. The reversal of 1721967 is 7691271.

It is not a de Polignac number, because 1721967 - 2⁶ = 1721903 is a prime.

1721967 is a lucky number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1721927) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2284 + ... + 2942.

It is an arithmetic number, because the mean of its divisors is an integer number (157080).

2^1721967 is an apocalyptic number.

1721967 is a deficient number, since it is larger than the sum of its proper divisors (791313).

1721967 is a wasteful number, since it uses less digits than its factorization.

1721967 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 742.

The product of its digits is 5292, while the sum is 33.

The square root of 1721967 is about 1312.2374023019. The cubic root of 1721967 is about 119.8601843821.

The spelling of 1721967 in words is "one million, seven hundred twenty-one thousand, nine hundred sixty-seven".