21215102622556 has 12 divisors (see below), whose sum is σ = 37126490368968. Its totient is φ = 10607533945712.

The previous prime is 21215102622551. The next prime is 21215102622559. The reversal of 21215102622556 is 65522620151212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21215102622551) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1366051 + ... + 6655546.

It is an arithmetic number, because the mean of its divisors is an integer number (3093874197414).

Almost surely, 2^{21215102622556} is an apocalyptic number.

It is an amenable number.

21215102622556 is a deficient number, since it is larger than the sum of its proper divisors (15911387746412).

21215102622556 is a wasteful number, since it uses less digits than its factorization.

21215102622556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8682788 (or 8682786 counting only the distinct ones).

The product of its (nonzero) digits is 144000, while the sum is 40.

Adding to 21215102622556 its reverse (65522620151212), we get a palindrome (86737722773768).

The spelling of 21215102622556 in words is "twenty-one trillion, two hundred fifteen billion, one hundred two million, six hundred twenty-two thousand, five hundred fifty-six".