101720820381 has 16 divisors (see below), whose sum is σ = 137572651008. Its totient is φ = 66841916400.

The previous prime is 101720820343. The next prime is 101720820437. The reversal of 101720820381 is 183028027101.

It is not a de Polignac number, because 101720820381 - 2¹³ = 101720812189 is a prime.

It is a super-3 number, since 3×101720820381³ (a number of 34 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (101724820381) 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 15 ways as a sum of consecutive naturals, for example, 817560 + ... + 933726.

It is an arithmetic number, because the mean of its divisors is an integer number (8598290688).

Almost surely, 2^101720820381 is an apocalyptic number.

It is an amenable number.

101720820381 is a deficient number, since it is larger than the sum of its proper divisors (35851830627).

101720820381 is a wasteful number, since it uses less digits than its factorization.

101720820381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120352.

The product of its (nonzero) digits is 5376, while the sum is 33.

Adding to 101720820381 its reverse (183028027101), we get a palindrome (284748847482).

The spelling of 101720820381 in words is "one hundred one billion, seven hundred twenty million, eight hundred twenty thousand, three hundred eighty-one".