71555406 has 64 divisors (see below), whose sum is σ = 165473280. Its totient is φ = 20442240.

The previous prime is 71555389. The next prime is 71555411. The reversal of 71555406 is 60455517.

It is a super-2 number, since 2×71555406² = 10240352255649672, which contains 22 as substring.

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 31 ways as a sum of consecutive naturals, for example, 78091 + ... + 79001.

It is an arithmetic number, because the mean of its divisors is an integer number (2585520).

Almost surely, 2^71555406 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71555406, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82736640).

71555406 is an abundant number, since it is smaller than the sum of its proper divisors (93917874).

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

71555406 is a wasteful number, since it uses less digits than its factorization.

71555406 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1001.

The product of its (nonzero) digits is 21000, while the sum is 33.

The square root of 71555406 is about 8459.0428536567. The cubic root of 71555406 is about 415.1587064156.

It can be divided in two parts, 7155 and 5406, that added together give a triangular number (12561 = T₁₅₈).

The spelling of 71555406 in words is "seventy-one million, five hundred fifty-five thousand, four hundred six".