71181138 has 32 divisors (see below), whose sum is σ = 168312960. Its totient is φ = 19635840.

The previous prime is 71181119. The next prime is 71181139. The reversal of 71181138 is 83118117.

It is a happy number.

It is a Curzon number.

It is a zygodrome in base 13.

It is not an unprimeable number, because it can be changed into a prime (71181139) 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, 28003 + ... + 30438.

It is an arithmetic number, because the mean of its divisors is an integer number (5259780).

Almost surely, 2^71181138 is an apocalyptic number.

71181138 is an abundant number, since it is smaller than the sum of its proper divisors (97131822).

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

71181138 is a wasteful number, since it uses less digits than its factorization.

71181138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58482.

The product of its digits is 1344, while the sum is 30.

The square root of 71181138 is about 8436.8914891683. The cubic root of 71181138 is about 414.4336164858.

It can be divided in two parts, 7118 and 1138, that added together give a triangular number (8256 = T₁₂₈).

The spelling of 71181138 in words is "seventy-one million, one hundred eighty-one thousand, one hundred thirty-eight".