21385253045 has 8 divisors (see below), whose sum is σ = 27636327096. Its totient is φ = 15792186816.

The previous prime is 21385253023. The next prime is 21385253093. The reversal of 21385253045 is 54035258312.

It can be written as a sum of positive squares in 4 ways, for example, as 3301996369 + 18083256676 = 57463^2 + 134474^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21385253045 is a prime.

It is a Duffinian number.

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 7 ways as a sum of consecutive naturals, for example, 164501882 + ... + 164502011.

It is an arithmetic number, because the mean of its divisors is an integer number (3454540887).

Almost surely, 2^21385253045 is an apocalyptic number.

It is an amenable number.

21385253045 is a deficient number, since it is larger than the sum of its proper divisors (6251074051).

21385253045 is a wasteful number, since it uses less digits than its factorization.

21385253045 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329003911.

The product of its (nonzero) digits is 144000, while the sum is 38.

The spelling of 21385253045 in words is "twenty-one billion, three hundred eighty-five million, two hundred fifty-three thousand, forty-five".