81036983421 has 6 divisors (see below), whose sum is σ = 117053420510. Its totient is φ = 54024655608.

The previous prime is 81036983383. The next prime is 81036983453. The reversal of 81036983421 is 12438963018.

It can be written as a sum of positive squares in only one way, i.e., 71510247396 + 9526736025 = 267414^2 + 97605^2 .

It is not a de Polignac number, because 81036983421 - 2¹¹ = 81036981373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81036983221) 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, 4502054626 + ... + 4502054643.

Almost surely, 2^81036983421 is an apocalyptic number.

It is an amenable number.

81036983421 is a deficient number, since it is larger than the sum of its proper divisors (36016437089).

81036983421 is a wasteful number, since it uses less digits than its factorization.

81036983421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9004109275 (or 9004109272 counting only the distinct ones).

The product of its (nonzero) digits is 248832, while the sum is 45.

The spelling of 81036983421 in words is "eighty-one billion, thirty-six million, nine hundred eighty-three thousand, four hundred twenty-one".