21250616512 has 84 divisors (see below), whose sum is σ = 43572329416. Its totient is φ = 10277406720.

The previous prime is 21250616473. The next prime is 21250616521. The reversal of 21250616512 is 21561605212.

It is a super-2 number, since 2×21250616512² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 88176712 + ... + 88176952.

Almost surely, 2^21250616512 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21250616512, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21786164708).

21250616512 is an abundant number, since it is smaller than the sum of its proper divisors (22321712904).

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

21250616512 is an equidigital number, since it uses as much as digits as its factorization.

21250616512 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654 (or 465 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 31.

The spelling of 21250616512 in words is "twenty-one billion, two hundred fifty million, six hundred sixteen thousand, five hundred twelve".