21445709594 has 4 divisors (see below), whose sum is σ = 32168564394. Its totient is φ = 10722854796.

The previous prime is 21445709563. The next prime is 21445709609. The reversal of 21445709594 is 49590754412.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15834950569 + 5610759025 = 125837^2 + 74905^2 .

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 as a sum of consecutive naturals, namely, 5361427397 + ... + 5361427400.

Almost surely, 2^21445709594 is an apocalyptic number.

21445709594 is a deficient number, since it is larger than the sum of its proper divisors (10722854800).

21445709594 is a wasteful number, since it uses less digits than its factorization.

21445709594 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10722854799.

The product of its (nonzero) digits is 1814400, while the sum is 50.

The spelling of 21445709594 in words is "twenty-one billion, four hundred forty-five million, seven hundred nine thousand, five hundred ninety-four".