1720455 has 16 divisors (see below), whose sum is σ = 3003264. Its totient is φ = 834080.

The previous prime is 1720429. The next prime is 1720457. The reversal of 1720455 is 5540271.

It is not a de Polignac number, because 1720455 - 2⁹ = 1719943 is a prime.

It is a Smith number, since the sum of its digits (24) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1720457) 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, 5049 + ... + 5378.

It is an arithmetic number, because the mean of its divisors is an integer number (187704).

2^1720455 is an apocalyptic number.

1720455 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1720455 is a deficient number, since it is larger than the sum of its proper divisors (1282809).

1720455 is a wasteful number, since it uses less digits than its factorization.

1720455 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10446.

The product of its (nonzero) digits is 1400, while the sum is 24.

The square root of 1720455 is about 1311.6611605136. The cubic root of 1720455 is about 119.8250924072.

The spelling of 1720455 in words is "one million, seven hundred twenty thousand, four hundred fifty-five".