71805920 has 72 divisors (see below), whose sum is σ = 175665672. Its totient is φ = 27736320.

The previous prime is 71805887. The next prime is 71805941. The reversal of 71805920 is 2950817.

It is a Harshad number since it is a multiple of its sum of digits (32).

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 153527 + ... + 153993.

It is an arithmetic number, because the mean of its divisors is an integer number (2439801).

Almost surely, 2^71805920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71805920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (87832836).

71805920 is an abundant number, since it is smaller than the sum of its proper divisors (103859752).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

71805920 is a wasteful number, since it uses less digits than its factorization.

71805920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 544 (or 505 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 71805920 is about 8473.8373833819. The cubic root of 71805920 is about 415.6426294744.

The spelling of 71805920 in words is "seventy-one million, eight hundred five thousand, nine hundred twenty".