21222001515 has 32 divisors (see below), whose sum is σ = 39891430656. Its totient is φ = 9497957760.

The previous prime is 21222001481. The next prime is 21222001589. The reversal of 21222001515 is 51510022212.

It is not a de Polignac number, because 21222001515 - 2⁷ = 21222001387 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21222001491 and 21222001500.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 4944709 + ... + 4948998.

It is an arithmetic number, because the mean of its divisors is an integer number (1246607208).

Almost surely, 2^21222001515 is an apocalyptic number.

21222001515 is a deficient number, since it is larger than the sum of its proper divisors (18669429141).

21222001515 is a wasteful number, since it uses less digits than its factorization.

21222001515 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9893739.

The product of its (nonzero) digits is 400, while the sum is 21.

Adding to 21222001515 its reverse (51510022212), we get a palindrome (72732023727).

The spelling of 21222001515 in words is "twenty-one billion, two hundred twenty-two million, one thousand, five hundred fifteen".