1720425820 has 24 divisors (see below), whose sum is σ = 3641347584. Its totient is φ = 682750656.

The previous prime is 1720425787. The next prime is 1720425859. The reversal of 1720425820 is 285240271.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 336127 + ... + 341206.

It is an arithmetic number, because the mean of its divisors is an integer number (151722816).

Almost surely, 2^1720425820 is an apocalyptic number.

1720425820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1720425820 is an abundant number, since it is smaller than the sum of its proper divisors (1920921764).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1720425820 is a wasteful number, since it uses less digits than its factorization.

1720425820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677469 (or 677467 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 31.

The square root of 1720425820 is about 41478.0161049200. The cubic root of 1720425820 is about 1198.2441496704.

The spelling of 1720425820 in words is "one billion, seven hundred twenty million, four hundred twenty-five thousand, eight hundred twenty".