36531814751981 has 2 divisors, whose sum is σ = 36531814751982. Its totient is φ = 36531814751980.

The previous prime is 36531814751977. The next prime is 36531814751983. The reversal of 36531814751981 is 18915741813563.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29128245849481 + 7403568902500 = 5397059^2 + 2720950^2 .

It is a cyclic number.

It is not a de Polignac number, because 36531814751981 - 2² = 36531814751977 is a prime.

It is a super-2 number, since 2×36531814751981² (a number of 28 digits) contains 22 as substring.

Together with 36531814751983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (36531814751983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 18265907375990 + 18265907375991.

It is an arithmetic number, because the mean of its divisors is an integer number (18265907375991).

Almost surely, 2^{36531814751981} is an apocalyptic number.

It is an amenable number.

36531814751981 is a deficient number, since it is larger than the sum of its proper divisors (1).

36531814751981 is an equidigital number, since it uses as much as digits as its factorization.

36531814751981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 21772800, while the sum is 62.

The spelling of 36531814751981 in words is "thirty-six trillion, five hundred thirty-one billion, eight hundred fourteen million, seven hundred fifty-one thousand, nine hundred eighty-one".