20733558381 has 12 divisors (see below), whose sum is σ = 30981179580. Its totient is φ = 13345738560.

The previous prime is 20733558367. The next prime is 20733558383. The reversal of 20733558381 is 18385533702.

20733558381 is a `hidden beast` number, since 20 + 73 + 3 + 558 + 3 + 8 + 1 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16168394025 + 4565164356 = 127155^2 + 67566^2 .

It is not a de Polignac number, because 20733558381 - 2¹⁹ = 20733034093 is a prime.

It is a super-2 number, since 2×20733558381² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20733558383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39719200 + ... + 39719721.

It is an arithmetic number, because the mean of its divisors is an integer number (2581764965).

Almost surely, 2^20733558381 is an apocalyptic number.

It is an amenable number.

20733558381 is a deficient number, since it is larger than the sum of its proper divisors (10247621199).

20733558381 is a wasteful number, since it uses less digits than its factorization.

20733558381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79438956 (or 79438953 counting only the distinct ones).

The product of its (nonzero) digits is 604800, while the sum is 45.

The spelling of 20733558381 in words is "twenty billion, seven hundred thirty-three million, five hundred fifty-eight thousand, three hundred eighty-one".