71612820 has 36 divisors (see below), whose sum is σ = 217226100. Its totient is φ = 19096704.

The previous prime is 71612813. The next prime is 71612833. The reversal of 71612820 is 2821617.

It can be written as a sum of positive squares in 2 ways, for example, as 16793604 + 54819216 = 4098^2 + 7404^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 198745 + ... + 199104.

Almost surely, 2^71612820 is an apocalyptic number.

It is an amenable number.

71612820 is an abundant number, since it is smaller than the sum of its proper divisors (145613280).

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

71612820 is a wasteful number, since it uses less digits than its factorization.

71612820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 397864 (or 397859 counting only the distinct ones).

The product of its (nonzero) digits is 1344, while the sum is 27.

The square root of 71612820 is about 8462.4358195498. The cubic root of 71612820 is about 415.2697138668.

The spelling of 71612820 in words is "seventy-one million, six hundred twelve thousand, eight hundred twenty".