21261650558 has 8 divisors (see below), whose sum is σ = 31963507200. Its totient is φ = 10607148160.

The previous prime is 21261650533. The next prime is 21261650561. The reversal of 21261650558 is 85505616212.

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

It is a super-3 number, since 3×21261650558³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

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 in 3 ways as a sum of consecutive naturals, for example, 11837438 + ... + 11839233.

It is an arithmetic number, because the mean of its divisors is an integer number (3995438400).

Almost surely, 2^21261650558 is an apocalyptic number.

21261650558 is a deficient number, since it is larger than the sum of its proper divisors (10701856642).

21261650558 is a wasteful number, since it uses less digits than its factorization.

21261650558 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23677122.

The product of its (nonzero) digits is 144000, while the sum is 41.

The spelling of 21261650558 in words is "twenty-one billion, two hundred sixty-one million, six hundred fifty thousand, five hundred fifty-eight".