81404263 has 8 divisors (see below), whose sum is σ = 82840320. Its totient is φ = 79974840.

The previous prime is 81404261. The next prime is 81404321. The reversal of 81404263 is 36240418.

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 81404263 - 2¹ = 81404261 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81404261) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27468 + ... + 30286.

It is an arithmetic number, because the mean of its divisors is an integer number (10355040).

Almost surely, 2^81404263 is an apocalyptic number.

81404263 is a deficient number, since it is larger than the sum of its proper divisors (1436057).

81404263 is a wasteful number, since it uses less digits than its factorization.

81404263 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3317.

The product of its (nonzero) digits is 4608, while the sum is 28.

The square root of 81404263 is about 9022.4311025355. The cubic root of 81404263 is about 433.3934894133.

It can be divided in two parts, 8140 and 4263, that added together give a triangular number (12403 = T₁₅₇).

The spelling of 81404263 in words is "eighty-one million, four hundred four thousand, two hundred sixty-three".