1720490640 has 160 divisors (see below), whose sum is σ = 5845447296. Its totient is φ = 415150080.

The previous prime is 1720490617. The next prime is 1720490647. The reversal of 1720490640 is 460940271.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (1720490647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 613722 + ... + 616518.

Almost surely, 2^1720490640 is an apocalyptic number.

1720490640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1720490640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2922723648).

1720490640 is an abundant number, since it is smaller than the sum of its proper divisors (4124956656).

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

1720490640 is a wasteful number, since it uses less digits than its factorization.

1720490640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3057 (or 3051 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 33.

The square root of 1720490640 is about 41478.7974753367. The cubic root of 1720490640 is about 1198.2591981174.

The spelling of 1720490640 in words is "one billion, seven hundred twenty million, four hundred ninety thousand, six hundred forty".