21256250655306 has 16 divisors (see below), whose sum is σ = 42512613781248. Its totient is φ = 7085398140000.

The previous prime is 21256250655293. The next prime is 21256250655331. The reversal of 21256250655306 is 60355605265212.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2121370 + ... + 6856581.

It is an arithmetic number, because the mean of its divisors is an integer number (2657038361328).

Almost surely, 2^{21256250655306} is an apocalyptic number.

21256250655306 is an abundant number, since it is smaller than the sum of its proper divisors (21256363125942).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21256250655306 is a wasteful number, since it uses less digits than its factorization.

21256250655306 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9372557.

The product of its (nonzero) digits is 3240000, while the sum is 48.

The spelling of 21256250655306 in words is "twenty-one trillion, two hundred fifty-six billion, two hundred fifty million, six hundred fifty-five thousand, three hundred six".