21387100558 has 4 divisors (see below), whose sum is σ = 32080650840. Its totient is φ = 10693550278.

The previous prime is 21387100543. The next prime is 21387100633. The reversal of 21387100558 is 85500178312.

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

It is a super-3 number, since 3×21387100558³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a self number, because there is not a number n which added to its sum of digits gives 21387100558.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5346775138 + ... + 5346775141.

It is an arithmetic number, because the mean of its divisors is an integer number (8020162710).

Almost surely, 2^21387100558 is an apocalyptic number.

21387100558 is a deficient number, since it is larger than the sum of its proper divisors (10693550282).

21387100558 is a wasteful number, since it uses less digits than its factorization.

21387100558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10693550281.

The product of its (nonzero) digits is 67200, while the sum is 40.

The spelling of 21387100558 in words is "twenty-one billion, three hundred eighty-seven million, one hundred thousand, five hundred fifty-eight".