71284720 has 40 divisors (see below), whose sum is σ = 178488576. Its totient is φ = 26320128.

The previous prime is 71284711. The next prime is 71284721. The reversal of 71284720 is 2748217.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-2 number, since 2×71284720² = 10163022610956800, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (71284721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33232 + ... + 35311.

Almost surely, 2^71284720 is an apocalyptic number.

It is an amenable number.

71284720 is an abundant number, since it is smaller than the sum of its proper divisors (107203856).

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

71284720 is a wasteful number, since it uses less digits than its factorization.

71284720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68569 (or 68563 counting only the distinct ones).

The product of its (nonzero) digits is 6272, while the sum is 31.

The square root of 71284720 is about 8443.0278928830. The cubic root of 71284720 is about 414.6345454499.

The spelling of 71284720 in words is "seventy-one million, two hundred eighty-four thousand, seven hundred twenty".