71396640 has 240 divisors, whose sum is σ = 288332352. Its totient is φ = 16298496.

The previous prime is 71396629. The next prime is 71396681. The reversal of 71396640 is 4669317.

71396640 is a `hidden beast` number, since 7 + 1 + 3 + 9 + 6 + 640 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 71396595 and 71396604.

It is an unprimeable number.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 90327 + ... + 91113.

Almost surely, 2^71396640 is an apocalyptic number.

71396640 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71396640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (144166176).

71396640 is an abundant number, since it is smaller than the sum of its proper divisors (216935712).

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

71396640 is a wasteful number, since it uses less digits than its factorization.

71396640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 821 (or 804 counting only the distinct ones).

The product of its (nonzero) digits is 27216, while the sum is 36.

The square root of 71396640 is about 8449.6532473232. The cubic root of 71396640 is about 414.8514298588.

The spelling of 71396640 in words is "seventy-one million, three hundred ninety-six thousand, six hundred forty".