56443978021 has 8 divisors (see below), whose sum is σ = 56631252600. Its totient is φ = 56256762048.

The previous prime is 56443978009. The next prime is 56443978033. The reversal of 56443978021 is 12087934465.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (56443978009) and next prime (56443978033).

It can be written as a sum of positive squares in 4 ways, for example, as 12081087396 + 44362890625 = 109914^2 + 210625^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 56443978021 - 2¹⁹ = 56443453733 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (56443978121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2791255 + ... + 2811403.

It is an arithmetic number, because the mean of its divisors is an integer number (7078906575).

It is a 1-persistent number, because it is pandigital, but 2⋅56443978021 = 112887956042 is not.

Almost surely, 2^56443978021 is an apocalyptic number.

It is an amenable number.

56443978021 is a deficient number, since it is larger than the sum of its proper divisors (187274579).

56443978021 is a wasteful number, since it uses less digits than its factorization.

56443978021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29303.

The product of its (nonzero) digits is 1451520, while the sum is 49.

The spelling of 56443978021 in words is "fifty-six billion, four hundred forty-three million, nine hundred seventy-eight thousand, twenty-one".