81006907 has 2 divisors, whose sum is σ = 81006908. Its totient is φ = 81006906.

The previous prime is 81006839. The next prime is 81006911. The reversal of 81006907 is 70960018.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-81006907 is a prime.

It is not a weakly prime, because it can be changed into another prime (81006917) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40503453 + 40503454.

It is an arithmetic number, because the mean of its divisors is an integer number (40503454).

Almost surely, 2^81006907 is an apocalyptic number.

81006907 is a deficient number, since it is larger than the sum of its proper divisors (1).

81006907 is an equidigital number, since it uses as much as digits as its factorization.

81006907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3024, while the sum is 31.

The square root of 81006907 is about 9000.3837140424. The cubic root of 81006907 is about 432.6871690362.

The spelling of 81006907 in words is "eighty-one million, six thousand, nine hundred seven".