71561216 has 26 divisors (see below), whose sum is σ = 143113152. Its totient is φ = 35778560.

The previous prime is 71561209. The next prime is 71561221. The reversal of 71561216 is 61216517.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4640 + ... + 12831.

It is an arithmetic number, because the mean of its divisors is an integer number (5504352).

Almost surely, 2^71561216 is an apocalyptic number.

It is an amenable number.

71561216 is a deficient number, since it is larger than the sum of its proper divisors (71551936).

71561216 is an equidigital number, since it uses as much as digits as its factorization.

71561216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17495 (or 17473 counting only the distinct ones).

The product of its digits is 2520, while the sum is 29.

The square root of 71561216 is about 8459.3862661543. The cubic root of 71561216 is about 415.1699424956.

The spelling of 71561216 in words is "seventy-one million, five hundred sixty-one thousand, two hundred sixteen".