71220864 has 128 divisors (see below), whose sum is σ = 222425280. Its totient is φ = 19906560.

The previous prime is 71220859. The next prime is 71220883. The reversal of 71220864 is 46802217.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×71220864² = 10144822937812992, which contains 22 as substring.

It is a hoax number, since the sum of its digits (30) coincides with the sum of the digits of its distinct prime factors.

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 15 ways as a sum of consecutive naturals, for example, 54264 + ... + 55560.

Almost surely, 2^71220864 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 71220864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (111212640).

71220864 is an abundant number, since it is smaller than the sum of its proper divisors (151204416).

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

71220864 is a wasteful number, since it uses less digits than its factorization.

71220864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1338 (or 1326 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 71220864 is about 8439.2454639026. The cubic root of 71220864 is about 414.5107002398.

The spelling of 71220864 in words is "seventy-one million, two hundred twenty thousand, eight hundred sixty-four".