81623245 has 16 divisors (see below), whose sum is σ = 109340352. Its totient is φ = 57980160.

The previous prime is 81623203. The next prime is 81623249. The reversal of 81623245 is 54232618.

It is not a de Polignac number, because 81623245 - 2⁷ = 81623117 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81623249) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14892 + ... + 19621.

It is an arithmetic number, because the mean of its divisors is an integer number (6833772).

Almost surely, 2^81623245 is an apocalyptic number.

It is an amenable number.

81623245 is a deficient number, since it is larger than the sum of its proper divisors (27717107).

81623245 is a wasteful number, since it uses less digits than its factorization.

81623245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34572.

The product of its digits is 11520, while the sum is 31.

The square root of 81623245 is about 9034.5583732687. The cubic root of 81623245 is about 433.7817590047.

It can be divided in two parts, 81 and 623245, that added together give a palindrome (623326).

The spelling of 81623245 in words is "eighty-one million, six hundred twenty-three thousand, two hundred forty-five".