21115333510 has 16 divisors (see below), whose sum is σ = 38032781472. Its totient is φ = 8440537600.

The previous prime is 21115333501. The next prime is 21115333511. The reversal of 21115333510 is 1533351112.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21115333511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 683611 + ... + 713830.

It is an arithmetic number, because the mean of its divisors is an integer number (2377048842).

Almost surely, 2^21115333510 is an apocalyptic number.

21115333510 is a deficient number, since it is larger than the sum of its proper divisors (16917447962).

21115333510 is a wasteful number, since it uses less digits than its factorization.

21115333510 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1398959.

The product of its (nonzero) digits is 1350, while the sum is 25.

Adding to 21115333510 its reverse (1533351112), we get a palindrome (22648684622).

The spelling of 21115333510 in words is "twenty-one billion, one hundred fifteen million, three hundred thirty-three thousand, five hundred ten".