1721323056420 has 144 divisors (see below), whose sum is σ = 5696536652352. Its totient is φ = 417252184320.

The previous prime is 1721323056407. The next prime is 1721323056433. The reversal of 1721323056420 is 246503231271.

1721323056420 is a `hidden beast` number, since 1 + 7 + 2 + 1 + 3 + 2 + 3 + 0 + 5 + 642 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (1721323056407) and next prime (1721323056433).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 25791814 + ... + 25858466.

It is an arithmetic number, because the mean of its divisors is an integer number (39559282308).

Almost surely, 2^{1721323056420} is an apocalyptic number.

1721323056420 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1721323056420 is an abundant number, since it is smaller than the sum of its proper divisors (3975213595932).

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

1721323056420 is a wasteful number, since it uses less digits than its factorization.

1721323056420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79722 (or 79717 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 36.

Adding to 1721323056420 its reverse (246503231271), we get a palindrome (1967826287691).

The spelling of 1721323056420 in words is "one trillion, seven hundred twenty-one billion, three hundred twenty-three million, fifty-six thousand, four hundred twenty".