21151224354664 has 16 divisors (see below), whose sum is σ = 41745837542400. Its totient is φ = 10019001010032.

The previous prime is 21151224354649. The next prime is 21151224354671. The reversal of 21151224354664 is 46645342215112.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 69576395752 + ... + 69576396055.

It is an arithmetic number, because the mean of its divisors is an integer number (2609114846400).

Almost surely, 2^{21151224354664} is an apocalyptic number.

It is an amenable number.

21151224354664 is a deficient number, since it is larger than the sum of its proper divisors (20594613187736).

21151224354664 is a wasteful number, since it uses less digits than its factorization.

21151224354664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139152791832 (or 139152791828 counting only the distinct ones).

The product of its digits is 1382400, while the sum is 46.

Adding to 21151224354664 its reverse (46645342215112), we get a palindrome (67796566569776).

The spelling of 21151224354664 in words is "twenty-one trillion, one hundred fifty-one billion, two hundred twenty-four million, three hundred fifty-four thousand, six hundred sixty-four".