84529151981 has 2 divisors, whose sum is σ = 84529151982. Its totient is φ = 84529151980.

The previous prime is 84529151977. The next prime is 84529152007. The reversal of 84529151981 is 18915192548.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 58810615081 + 25718536900 = 242509^2 + 160370^2 .

It is a cyclic number.

It is not a de Polignac number, because 84529151981 - 2² = 84529151977 is a prime.

It is a super-2 number, since 2×84529151981² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (84529151951) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 42264575990 + 42264575991.

It is an arithmetic number, because the mean of its divisors is an integer number (42264575991).

Almost surely, 2^84529151981 is an apocalyptic number.

It is an amenable number.

84529151981 is a deficient number, since it is larger than the sum of its proper divisors (1).

84529151981 is an equidigital number, since it uses as much as digits as its factorization.

84529151981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1036800, while the sum is 53.

The spelling of 84529151981 in words is "eighty-four billion, five hundred twenty-nine million, one hundred fifty-one thousand, nine hundred eighty-one".