81234473501 has 2 divisors, whose sum is σ = 81234473502. Its totient is φ = 81234473500.

The previous prime is 81234473479. The next prime is 81234473519. The reversal of 81234473501 is 10537443218.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 43817374276 + 37417099225 = 209326^2 + 193435^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81234473501 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81234473521) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40617236750 + 40617236751.

It is an arithmetic number, because the mean of its divisors is an integer number (40617236751).

Almost surely, 2^81234473501 is an apocalyptic number.

It is an amenable number.

81234473501 is a deficient number, since it is larger than the sum of its proper divisors (1).

81234473501 is an equidigital number, since it uses as much as digits as its factorization.

81234473501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80640, while the sum is 38.

The spelling of 81234473501 in words is "eighty-one billion, two hundred thirty-four million, four hundred seventy-three thousand, five hundred one".