21036586394 has 8 divisors (see below), whose sum is σ = 31556073108. Its totient is φ = 10517895360.

The previous prime is 21036586357. The next prime is 21036586423. The reversal of 21036586394 is 49368563012.

It can be written as a sum of positive squares in 2 ways, for example, as 18032998369 + 3003588025 = 134287^2 + 54805^2 .

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

It is a super-3 number, since 3×21036586394³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 127727 + ... + 241634.

Almost surely, 2^21036586394 is an apocalyptic number.

21036586394 is a deficient number, since it is larger than the sum of its proper divisors (10519486714).

21036586394 is a wasteful number, since it uses less digits than its factorization.

21036586394 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 397840.

The product of its (nonzero) digits is 933120, while the sum is 47.

The spelling of 21036586394 in words is "twenty-one billion, thirty-six million, five hundred eighty-six thousand, three hundred ninety-four".