21215116630 has 16 divisors (see below), whose sum is σ = 38189114064. Its totient is φ = 8485623520.

The previous prime is 21215116597. The next prime is 21215116649. The reversal of 21215116630 is 3661151212.

It is a super-3 number, since 3×21215116630³ (a number of 32 digits) contains 333 as substring.

It is a congruent 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, 229464 + ... + 308356.

It is an arithmetic number, because the mean of its divisors is an integer number (2386819629).

Almost surely, 2^21215116630 is an apocalyptic number.

21215116630 is a deficient number, since it is larger than the sum of its proper divisors (16973997434).

21215116630 is a wasteful number, since it uses less digits than its factorization.

21215116630 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105791.

The product of its (nonzero) digits is 2160, while the sum is 28.

Adding to 21215116630 its reverse (3661151212), we get a palindrome (24876267842).

The spelling of 21215116630 in words is "twenty-one billion, two hundred fifteen million, one hundred sixteen thousand, six hundred thirty".