81026643 has 8 divisors (see below), whose sum is σ = 108129168. Its totient is φ = 53970944.

The previous prime is 81026629. The next prime is 81026681. The reversal of 81026643 is 34662018.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 81026643 - 2¹² = 81022547 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81026643.

It is not an unprimeable number, because it can be changed into a prime (81026683) 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, 7446 + ... + 14747.

It is an arithmetic number, because the mean of its divisors is an integer number (13516146).

Almost surely, 2^81026643 is an apocalyptic number.

81026643 is a deficient number, since it is larger than the sum of its proper divisors (27102525).

81026643 is a wasteful number, since it uses less digits than its factorization.

81026643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23413.

The product of its (nonzero) digits is 6912, while the sum is 30.

The square root of 81026643 is about 9001.4800449704. The cubic root of 81026643 is about 432.7223052194.

The spelling of 81026643 in words is "eighty-one million, twenty-six thousand, six hundred forty-three".