1720724 has 12 divisors (see below), whose sum is σ = 3024084. Its totient is φ = 856704.

The previous prime is 1720711. The next prime is 1720769. The reversal of 1720724 is 4270271.

1720724 is an esthetic number in base 9, because in such base its adjacent digits differ by 1.

It can be written as a sum of positive squares in 2 ways, for example, as 232324 + 1488400 = 482^2 + 1220^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 1720724.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 332 + ... + 1884.

It is an arithmetic number, because the mean of its divisors is an integer number (252007).

2^1720724 is an apocalyptic number.

It is an amenable number.

1720724 is a deficient number, since it is larger than the sum of its proper divisors (1303360).

1720724 is a wasteful number, since it uses less digits than its factorization.

1720724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1834 (or 1832 counting only the distinct ones).

The product of its (nonzero) digits is 784, while the sum is 23.

The square root of 1720724 is about 1311.7636982323. The cubic root of 1720724 is about 119.8313371254.

Adding to 1720724 its reverse (4270271), we get a palindrome (5990995).

The spelling of 1720724 in words is "one million, seven hundred twenty thousand, seven hundred twenty-four".