1721057 has 8 divisors (see below), whose sum is σ = 1899240. Its totient is φ = 1549440.

The previous prime is 1721023. The next prime is 1721081. The reversal of 1721057 is 7501271.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 59536 + 1661521 = 244^2 + 1289^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1721057 - 2¹⁴ = 1704673 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1721257) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1082 + ... + 2147.

It is an arithmetic number, because the mean of its divisors is an integer number (237405).

2^1721057 is an apocalyptic number.

It is an amenable number.

1721057 is a deficient number, since it is larger than the sum of its proper divisors (178183).

1721057 is a wasteful number, since it uses less digits than its factorization.

1721057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3283.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 1721057 is about 1311.8906204406. The cubic root of 1721057 is about 119.8390666744.

The spelling of 1721057 in words is "one million, seven hundred twenty-one thousand, fifty-seven".