81124207 has 2 divisors, whose sum is σ = 81124208. Its totient is φ = 81124206.

The previous prime is 81124201. The next prime is 81124217. The reversal of 81124207 is 70242118.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 81124207 - 2¹¹ = 81122159 is a prime.

It is a super-2 number, since 2×81124207² = 13162273922757698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (81124201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40562103 + 40562104.

It is an arithmetic number, because the mean of its divisors is an integer number (40562104).

Almost surely, 2^81124207 is an apocalyptic number.

81124207 is a deficient number, since it is larger than the sum of its proper divisors (1).

81124207 is an equidigital number, since it uses as much as digits as its factorization.

81124207 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 25.

The square root of 81124207 is about 9006.8977456170. The cubic root of 81124207 is about 432.8959155440.

The spelling of 81124207 in words is "eighty-one million, one hundred twenty-four thousand, two hundred seven".