21424450515 has 32 divisors (see below), whose sum is σ = 39087510336. Its totient is φ = 9926983680.

The previous prime is 21424450477. The next prime is 21424450529. The reversal of 21424450515 is 51505442412.

It is a happy number.

It is not a de Polignac number, because 21424450515 - 2⁷ = 21424450387 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3228126 + ... + 3234755.

It is an arithmetic number, because the mean of its divisors is an integer number (1221484698).

Almost surely, 2^21424450515 is an apocalyptic number.

21424450515 is a deficient number, since it is larger than the sum of its proper divisors (17663059821).

21424450515 is a wasteful number, since it uses less digits than its factorization.

21424450515 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6462919.

The product of its (nonzero) digits is 32000, while the sum is 33.

Adding to 21424450515 its reverse (51505442412), we get a palindrome (72929892927).

The spelling of 21424450515 in words is "twenty-one billion, four hundred twenty-four million, four hundred fifty thousand, five hundred fifteen".