101639178481 has 3 divisors (see below), whose sum is σ = 101639497291. Its totient is φ = 101638859672.

The previous prime is 101639178479. The next prime is 101639178517. The reversal of 101639178481 is 184871936101.

The square root of 101639178481 is 318809.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 184871936101 = 149 ⋅1240751249.

It can be written as a sum of positive squares in only one way, i.e., 78181192881 + 23457985600 = 279609^2 + 153160^2 .

It is not a de Polignac number, because 101639178481 - 2¹ = 101639178479 is a prime.

It is a super-2 number, since 2×101639178481² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (101639178181) 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 2 ways as a sum of consecutive naturals, for example, 159405 + ... + 478213.

Almost surely, 2^101639178481 is an apocalyptic number.

101639178481 is the 318809-th square number.

101639178481 is the 159405-th centered octagonal number.

It is an amenable number.

101639178481 is a deficient number, since it is larger than the sum of its proper divisors (318810).

101639178481 is an frugal number, since it uses more digits than its factorization.

101639178481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637618 (or 318809 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 49.

Multiplying 101639178481 by its sum of digits (49), we get a square (4980319745569 = 2231663²).

The spelling of 101639178481 in words is "one hundred one billion, six hundred thirty-nine million, one hundred seventy-eight thousand, four hundred eighty-one".