21394044558 has 24 divisors (see below), whose sum is σ = 46612729800. Its totient is φ = 7091507184.

The previous prime is 21394044491. The next prime is 21394044571. The reversal of 21394044558 is 85544049312.

21394044558 is a `hidden beast` number, since 2 + 1 + 3 + 94 + 0 + 4 + 4 + 558 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3316773 + ... + 3323216.

It is an arithmetic number, because the mean of its divisors is an integer number (1942197075).

Almost surely, 2^21394044558 is an apocalyptic number.

21394044558 is an abundant number, since it is smaller than the sum of its proper divisors (25218685242).

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

21394044558 is a wasteful number, since it uses less digits than its factorization.

21394044558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6640176 (or 6640173 counting only the distinct ones).

The product of its (nonzero) digits is 691200, while the sum is 45.

The spelling of 21394044558 in words is "twenty-one billion, three hundred ninety-four million, forty-four thousand, five hundred fifty-eight".