1720821036 has 96 divisors (see below), whose sum is σ = 4586029056. Its totient is φ = 497448000.

The previous prime is 1720821029. The next prime is 1720821079. The reversal of 1720821036 is 6301280271.

It is a super-2 number, since 2×1720821036² = 5922450075880226592, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1720820994 and 1720821012.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 287571 + ... + 293493.

It is an arithmetic number, because the mean of its divisors is an integer number (47771136).

Almost surely, 2^1720821036 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1720821036, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2293014528).

1720821036 is an abundant number, since it is smaller than the sum of its proper divisors (2865208020).

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

1720821036 is a wasteful number, since it uses less digits than its factorization.

1720821036 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6043 (or 6041 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 30.

The square root of 1720821036 is about 41482.7799936311. The cubic root of 1720821036 is about 1198.3358961431.

The spelling of 1720821036 in words is "one billion, seven hundred twenty million, eight hundred twenty-one thousand, thirty-six".