531211816 has 8 divisors (see below), whose sum is σ = 996022170. Its totient is φ = 265605904.

The previous prime is 531211781. The next prime is 531211831. The reversal of 531211816 is 618112135.

It can be written as a sum of positive squares in only one way, i.e., 330876100 + 200335716 = 18190^2 + 14154^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33200731 + ... + 33200746.

Almost surely, 2^531211816 is an apocalyptic number.

It is an amenable number.

531211816 is a deficient number, since it is larger than the sum of its proper divisors (464810354).

531211816 is a wasteful number, since it uses less digits than its factorization.

531211816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66401483 (or 66401479 counting only the distinct ones).

The product of its digits is 1440, while the sum is 28.

The square root of 531211816 is about 23048.0328010874. The cubic root of 531211816 is about 809.8835457232.

The spelling of 531211816 in words is "five hundred thirty-one million, two hundred eleven thousand, eight hundred sixteen".