71811047 has 16 divisors (see below), whose sum is σ = 92620800. Its totient is φ = 54025440.

The previous prime is 71811029. The next prime is 71811059. The reversal of 71811047 is 74011817.

It is not a de Polignac number, because 71811047 - 2¹⁶ = 71745511 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71811067) 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, 13847 + ... + 18312.

It is an arithmetic number, because the mean of its divisors is an integer number (5788800).

Almost surely, 2^71811047 is an apocalyptic number.

71811047 is a gapful number since it is divisible by the number (77) formed by its first and last digit.

71811047 is a deficient number, since it is larger than the sum of its proper divisors (20809753).

71811047 is a wasteful number, since it uses less digits than its factorization.

71811047 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32206.

The product of its (nonzero) digits is 1568, while the sum is 29.

The square root of 71811047 is about 8474.1398973583. The cubic root of 71811047 is about 415.6525216441.

It can be divided in two parts, 7181 and 1047, that added together give a palindrome (8228).

The spelling of 71811047 in words is "seventy-one million, eight hundred eleven thousand, forty-seven".