81896597 has 2 divisors, whose sum is σ = 81896598. Its totient is φ = 81896596.

The previous prime is 81896569. The next prime is 81896603. The reversal of 81896597 is 79569818.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 58461316 + 23435281 = 7646^2 + 4841^2 .

It is a cyclic number.

It is not a de Polignac number, because 81896597 - 2⁸ = 81896341 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81896567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40948298 + 40948299.

It is an arithmetic number, because the mean of its divisors is an integer number (40948299).

Almost surely, 2^81896597 is an apocalyptic number.

It is an amenable number.

81896597 is a deficient number, since it is larger than the sum of its proper divisors (1).

81896597 is an equidigital number, since it uses as much as digits as its factorization.

81896597 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 53.

The square root of 81896597 is about 9049.6738615267. The cubic root of 81896597 is about 434.2654569587.

The spelling of 81896597 in words is "eighty-one million, eight hundred ninety-six thousand, five hundred ninety-seven".