21024215345 has 16 divisors (see below), whose sum is σ = 29763314688. Its totient is φ = 13951552320.

The previous prime is 21024215273. The next prime is 21024215393. The reversal of 21024215345 is 54351242012.

It is not a de Polignac number, because 21024215345 - 2¹⁸ = 21023953201 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9687494 + ... + 9689663.

It is an arithmetic number, because the mean of its divisors is an integer number (1860207168).

Almost surely, 2^21024215345 is an apocalyptic number.

It is an amenable number.

21024215345 is a deficient number, since it is larger than the sum of its proper divisors (8739099343).

21024215345 is a wasteful number, since it uses less digits than its factorization.

21024215345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19377200.

The product of its (nonzero) digits is 9600, while the sum is 29.

Adding to 21024215345 its reverse (54351242012), we get a palindrome (75375457357).

The spelling of 21024215345 in words is "twenty-one billion, twenty-four million, two hundred fifteen thousand, three hundred forty-five".