21305522402 has 8 divisors (see below), whose sum is σ = 32010419676. Its totient is φ = 10635382512.

The previous prime is 21305522333. The next prime is 21305522419. The reversal of 21305522402 is 20422550312.

It can be written as a sum of positive squares in 2 ways, for example, as 18911475361 + 2394047041 = 137519^2 + 48929^2 .

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

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, 8687813 + ... + 8690264.

Almost surely, 2^21305522402 is an apocalyptic number.

21305522402 is a deficient number, since it is larger than the sum of its proper divisors (10704897274).

21305522402 is a wasteful number, since it uses less digits than its factorization.

21305522402 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17378692.

The product of its (nonzero) digits is 4800, while the sum is 26.

The spelling of 21305522402 in words is "twenty-one billion, three hundred five million, five hundred twenty-two thousand, four hundred two".