21616505426 has 8 divisors (see below), whose sum is σ = 33834530304. Its totient is φ = 10338328660.

The previous prime is 21616505369. The next prime is 21616505441. The reversal of 21616505426 is 62450561612.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21616505426.

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, 234961970 + ... + 234962061.

It is an arithmetic number, because the mean of its divisors is an integer number (4229316288).

Almost surely, 2^21616505426 is an apocalyptic number.

21616505426 is a deficient number, since it is larger than the sum of its proper divisors (12218024878).

21616505426 is a wasteful number, since it uses less digits than its factorization.

21616505426 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 469924056.

The product of its (nonzero) digits is 86400, while the sum is 38.

The spelling of 21616505426 in words is "twenty-one billion, six hundred sixteen million, five hundred five thousand, four hundred twenty-six".