21377853243 has 24 divisors (see below), whose sum is σ = 32708286000. Its totient is φ = 13408326144.

The previous prime is 21377853221. The next prime is 21377853257. The reversal of 21377853243 is 34235877312.

It is a happy number.

21377853243 is a `hidden beast` number, since 2 + 1 + 3 + 7 + 78 + 532 + 43 = 666.

It is not a de Polignac number, because 21377853243 - 2¹⁴ = 21377836859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21377853143) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 387063 + ... + 438831.

It is an arithmetic number, because the mean of its divisors is an integer number (1362845250).

Almost surely, 2^21377853243 is an apocalyptic number.

21377853243 is a deficient number, since it is larger than the sum of its proper divisors (11330432757).

21377853243 is a wasteful number, since it uses less digits than its factorization.

21377853243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 54491 (or 54488 counting only the distinct ones).

The product of its digits is 846720, while the sum is 45.

The spelling of 21377853243 in words is "twenty-one billion, three hundred seventy-seven million, eight hundred fifty-three thousand, two hundred forty-three".