1720821332 has 12 divisors (see below), whose sum is σ = 3084887316. Its totient is φ = 839424960.

The previous prime is 1720821329. The next prime is 1720821341. The reversal of 1720821332 is 2331280271.

It can be written as a sum of positive squares in 2 ways, for example, as 716311696 + 1004509636 = 26764^2 + 31694^2 .

It is a super-2 number, since 2×1720821332² = 5922452113332508448, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1720821295 and 1720821304.

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, 5246243 + ... + 5246570.

It is an arithmetic number, because the mean of its divisors is an integer number (257073943).

Almost surely, 2^1720821332 is an apocalyptic number.

It is an amenable number.

1720821332 is a deficient number, since it is larger than the sum of its proper divisors (1364065984).

1720821332 is a wasteful number, since it uses less digits than its factorization.

1720821332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10492858 (or 10492856 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 29.

The square root of 1720821332 is about 41482.7835613764. The cubic root of 1720821332 is about 1198.3359648521.

The spelling of 1720821332 in words is "one billion, seven hundred twenty million, eight hundred twenty-one thousand, three hundred thirty-two".