81265207 has 4 divisors (see below), whose sum is σ = 81341056. Its totient is φ = 81189360.

The previous prime is 81265201. The next prime is 81265211. The reversal of 81265207 is 70256218.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 81265207 - 2²³ = 72876599 is a prime.

It is a super-3 number, since 3×81265207³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81265201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36294 + ... + 38467.

It is an arithmetic number, because the mean of its divisors is an integer number (20335264).

Almost surely, 2^81265207 is an apocalyptic number.

81265207 is a deficient number, since it is larger than the sum of its proper divisors (75849).

81265207 is a wasteful number, since it uses less digits than its factorization.

81265207 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75848.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 81265207 is about 9014.7216817825. The cubic root of 81265207 is about 433.1465723142.

The spelling of 81265207 in words is "eighty-one million, two hundred sixty-five thousand, two hundred seven".