21205650212 has 6 divisors (see below), whose sum is σ = 37109887878. Its totient is φ = 10602825104.

The previous prime is 21205650211. The next prime is 21205650217.

21205650212 is nontrivially palindromic in base 10.

It can be written as a sum of positive squares in only one way, i.e., 12370778176 + 8834872036 = 111224^2 + 93994^2 .

It is not an unprimeable number, because it can be changed into a prime (21205650211) by changing a digit.

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 as a sum of consecutive naturals, namely, 2650706273 + ... + 2650706280.

It is an arithmetic number, because the mean of its divisors is an integer number (6184981313).

Almost surely, 2^21205650212 is an apocalyptic number.

It is an amenable number.

21205650212 is a deficient number, since it is larger than the sum of its proper divisors (15904237666).

21205650212 is a wasteful number, since it uses less digits than its factorization.

21205650212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5301412557 (or 5301412555 counting only the distinct ones).

The product of its (nonzero) digits is 2400, while the sum is 26.

The spelling of 21205650212 in words is "twenty-one billion, two hundred five million, six hundred fifty thousand, two hundred twelve".