21061143873 has 24 divisors (see below), whose sum is σ = 37928294976. Its totient is φ = 10940853600.

The previous prime is 21061143863. The next prime is 21061143911. The reversal of 21061143873 is 37834116012.

It is a happy number.

21061143873 is a `hidden beast` number, since 2 + 1 + 0 + 611 + 4 + 38 + 7 + 3 = 666.

It is not a de Polignac number, because 21061143873 - 2⁹ = 21061143361 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21061143823) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15194938 + ... + 15196323.

It is an arithmetic number, because the mean of its divisors is an integer number (1580345624).

Almost surely, 2^21061143873 is an apocalyptic number.

It is an amenable number.

21061143873 is a deficient number, since it is larger than the sum of its proper divisors (16867151103).

21061143873 is a wasteful number, since it uses less digits than its factorization.

21061143873 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30391285 (or 30391282 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

Adding to 21061143873 its reverse (37834116012), we get a palindrome (58895259885).

The spelling of 21061143873 in words is "twenty-one billion, sixty-one million, one hundred forty-three thousand, eight hundred seventy-three".