44394540021 has 40 divisors (see below), whose sum is σ = 73349447864. Its totient is φ = 26581322880.

The previous prime is 44394540011. The next prime is 44394540097. The reversal of 44394540021 is 12004549344.

44394540021 is a `hidden beast` number, since 4 + 4 + 3 + 94 + 540 + 0 + 21 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 853457796 + 43541082225 = 29214^2 + 208665^2 .

It is a de Polignac number, because none of the positive numbers 2^k-44394540021 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (44394540011) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 530770 + ... + 608691.

Almost surely, 2^44394540021 is an apocalyptic number.

It is an amenable number.

44394540021 is a deficient number, since it is larger than the sum of its proper divisors (28954907843).

44394540021 is a wasteful number, since it uses less digits than its factorization.

44394540021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1139523 (or 1139514 counting only the distinct ones).

The product of its (nonzero) digits is 69120, while the sum is 36.

The spelling of 44394540021 in words is "forty-four billion, three hundred ninety-four million, five hundred forty thousand, twenty-one".