21116645336740 has 48 divisors (see below), whose sum is σ = 44907468883200. Its totient is φ = 8339518317312.

The previous prime is 21116645336713. The next prime is 21116645336777. The reversal of 21116645336740 is 4763354661112.

It is a happy number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 68064891 + ... + 68374429.

It is an arithmetic number, because the mean of its divisors is an integer number (935572268400).

Almost surely, 2^{21116645336740} is an apocalyptic number.

21116645336740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21116645336740 is an abundant number, since it is smaller than the sum of its proper divisors (23790823546460).

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

21116645336740 is a wasteful number, since it uses less digits than its factorization.

21116645336740 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352804 (or 352802 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 49.

Adding to 21116645336740 its reverse (4763354661112), we get a palindrome (25879999997852).

The spelling of 21116645336740 in words is "twenty-one trillion, one hundred sixteen billion, six hundred forty-five million, three hundred thirty-six thousand, seven hundred forty".