71855421 has 8 divisors (see below), whose sum is σ = 104517024. Its totient is φ = 43548720.

The previous prime is 71855393. The next prime is 71855429. The reversal of 71855421 is 12455817.

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

It is not a de Polignac number, because 71855421 - 2¹⁰ = 71854397 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 2177437 = 71855421 / (7 + 1 + 8 + 5 + 5 + 4 + 2 + 1).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71855429) 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, 1088686 + ... + 1088751.

It is an arithmetic number, because the mean of its divisors is an integer number (13064628).

Almost surely, 2^71855421 is an apocalyptic number.

It is an amenable number.

71855421 is a deficient number, since it is larger than the sum of its proper divisors (32661603).

71855421 is a wasteful number, since it uses less digits than its factorization.

71855421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2177451.

The product of its digits is 11200, while the sum is 33.

The square root of 71855421 is about 8476.7576938355. The cubic root of 71855421 is about 415.7381183502.

The spelling of 71855421 in words is "seventy-one million, eight hundred fifty-five thousand, four hundred twenty-one".