1721425 has 12 divisors (see below), whose sum is σ = 2193436. Its totient is φ = 1339200.

The previous prime is 1721417. The next prime is 1721441. The reversal of 1721425 is 5241271.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 141376 + 1580049 = 376^2 + 1257^2 .

It is not a de Polignac number, because 1721425 - 2³ = 1721417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1721396 and 1721405.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6 + ... + 1855.

2^1721425 is an apocalyptic number.

It is an amenable number.

1721425 is a deficient number, since it is larger than the sum of its proper divisors (472011).

1721425 is a wasteful number, since it uses less digits than its factorization.

1721425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1908 (or 1903 counting only the distinct ones).

The product of its digits is 560, while the sum is 22.

The square root of 1721425 is about 1312.0308685393. The cubic root of 1721425 is about 119.8476074788.

Adding to 1721425 its reverse (5241271), we get a palindrome (6962696).

The spelling of 1721425 in words is "one million, seven hundred twenty-one thousand, four hundred twenty-five".