21819426594 has 96 divisors (see below), whose sum is σ = 53219358720. Its totient is φ = 5840823552.

The previous prime is 21819426581. The next prime is 21819426599. The reversal of 21819426594 is 49562491812.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is not an unprimeable number, because it can be changed into a prime (21819426599) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2751367 + ... + 2759285.

It is an arithmetic number, because the mean of its divisors is an integer number (554368320).

Almost surely, 2^21819426594 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21819426594, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26609679360).

21819426594 is an abundant number, since it is smaller than the sum of its proper divisors (31399932126).

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

21819426594 is a wasteful number, since it uses less digits than its factorization.

21819426594 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8192 (or 8175 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 51.

The spelling of 21819426594 in words is "twenty-one billion, eight hundred nineteen million, four hundred twenty-six thousand, five hundred ninety-four".