21605357233071 has 6 divisors (see below), whose sum is σ = 31207738225560. Its totient is φ = 14403571488708.

The previous prime is 21605357233037. The next prime is 21605357233087. The reversal of 21605357233071 is 17033275350612.

21605357233071 is a `hidden beast` number, since 2 + 1 + 6 + 0 + 5 + 3 + 572 + 3 + 3 + 0 + 71 = 666.

It is not a de Polignac number, because 21605357233071 - 2¹¹ = 21605357231023 is a prime.

It is a super-2 number, since 2×21605357233071² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21605357233091) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1200297624051 + ... + 1200297624068.

It is an arithmetic number, because the mean of its divisors is an integer number (5201289704260).

Almost surely, 2^{21605357233071} is an apocalyptic number.

21605357233071 is a deficient number, since it is larger than the sum of its proper divisors (9602380992489).

21605357233071 is a wasteful number, since it uses less digits than its factorization.

21605357233071 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2400595248125 (or 2400595248122 counting only the distinct ones).

The product of its (nonzero) digits is 793800, while the sum is 45.

The spelling of 21605357233071 in words is "twenty-one trillion, six hundred five billion, three hundred fifty-seven million, two hundred thirty-three thousand, seventy-one".