81364628 has 24 divisors (see below), whose sum is σ = 148108800. Its totient is φ = 39076128.

The previous prime is 81364627. The next prime is 81364681. The reversal of 81364628 is 82646318.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 81364591 and 81364600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81364627) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8213 + ... + 15171.

It is an arithmetic number, because the mean of its divisors is an integer number (6171200).

Almost surely, 2^81364628 is an apocalyptic number.

It is an amenable number.

81364628 is a deficient number, since it is larger than the sum of its proper divisors (66744172).

81364628 is a wasteful number, since it uses less digits than its factorization.

81364628 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7079 (or 7077 counting only the distinct ones).

The product of its digits is 55296, while the sum is 38.

The square root of 81364628 is about 9020.2343650262. The cubic root of 81364628 is about 433.3231395367.

The spelling of 81364628 in words is "eighty-one million, three hundred sixty-four thousand, six hundred twenty-eight".