21100340245 has 16 divisors (see below), whose sum is σ = 27463747248. Its totient is φ = 15499816960.

The previous prime is 21100340221. The next prime is 21100340269. The reversal of 21100340245 is 54204300112.

It is an interprime number because it is at equal distance from previous prime (21100340221) and next prime (21100340269).

It can be written as a sum of positive squares in 8 ways, for example, as 345327889 + 20755012356 = 18583^2 + 144066^2 .

It is not a de Polignac number, because 21100340245 - 2⁵ = 21100340213 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3023824 + ... + 3030793.

It is an arithmetic number, because the mean of its divisors is an integer number (1716484203).

Almost surely, 2^21100340245 is an apocalyptic number.

It is an amenable number.

21100340245 is a deficient number, since it is larger than the sum of its proper divisors (6363407003).

21100340245 is a wasteful number, since it uses less digits than its factorization.

21100340245 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6054680.

The product of its (nonzero) digits is 960, while the sum is 22.

Adding to 21100340245 its reverse (54204300112), we get a palindrome (75304640357).

The spelling of 21100340245 in words is "twenty-one billion, one hundred million, three hundred forty thousand, two hundred forty-five".