651019816 has 16 divisors (see below), whose sum is σ = 1240673940. Its totient is φ = 320173440.

The previous prime is 651019813. The next prime is 651019823. The reversal of 651019816 is 618910156.

It can be written as a sum of positive squares in 2 ways, for example, as 539632900 + 111386916 = 23230^2 + 10554^2 .

It is not an unprimeable number, because it can be changed into a prime (651019813) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 666541 + ... + 667516.

Almost surely, 2^651019816 is an apocalyptic number.

It is an amenable number.

651019816 is a deficient number, since it is larger than the sum of its proper divisors (589654124).

651019816 is a wasteful number, since it uses less digits than its factorization.

651019816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1334124 (or 1334120 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 37.

The square root of 651019816 is about 25515.0899665277. The cubic root of 651019816 is about 866.6918965699.

The spelling of 651019816 in words is "six hundred fifty-one million, nineteen thousand, eight hundred sixteen".