81269101 has 2 divisors, whose sum is σ = 81269102. Its totient is φ = 81269100.

The previous prime is 81269081. The next prime is 81269113. The reversal of 81269101 is 10196218.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80460900 + 808201 = 8970^2 + 899^2 .

It is a cyclic number.

It is not a de Polignac number, because 81269101 - 2⁹ = 81268589 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81269101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81269171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40634550 + 40634551.

It is an arithmetic number, because the mean of its divisors is an integer number (40634551).

Almost surely, 2^81269101 is an apocalyptic number.

It is an amenable number.

81269101 is a deficient number, since it is larger than the sum of its proper divisors (1).

81269101 is an equidigital number, since it uses as much as digits as its factorization.

81269101 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 28.

The square root of 81269101 is about 9014.9376592409. The cubic root of 81269101 is about 433.1534905919.

The spelling of 81269101 in words is "eighty-one million, two hundred sixty-nine thousand, one hundred one".