21650555012 has 6 divisors (see below), whose sum is σ = 37888471278. Its totient is φ = 10825277504.

The previous prime is 21650554999. The next prime is 21650555053. The reversal of 21650555012 is 21055505612.

It can be written as a sum of positive squares in only one way, i.e., 21649002496 + 1552516 = 147136^2 + 1246^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21650555012.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2706319373 + ... + 2706319380.

It is an arithmetic number, because the mean of its divisors is an integer number (6314745213).

Almost surely, 2^21650555012 is an apocalyptic number.

It is an amenable number.

21650555012 is a deficient number, since it is larger than the sum of its proper divisors (16237916266).

21650555012 is a wasteful number, since it uses less digits than its factorization.

21650555012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5412638757 (or 5412638755 counting only the distinct ones).

The product of its (nonzero) digits is 15000, while the sum is 32.

The spelling of 21650555012 in words is "twenty-one billion, six hundred fifty million, five hundred fifty-five thousand, twelve".