651103668 has 18 divisors (see below), whose sum is σ = 1645845474. Its totient is φ = 217034544.

The previous prime is 651103639. The next prime is 651103669. The reversal of 651103668 is 866301156.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 492041124 + 159062544 = 22182^2 + 12612^2 .

It is a tau number, because it is divible by the number of its divisors (18).

It is a Harshad number since it is a multiple of its sum of digits (36), and also a Moran number because the ratio is a prime number: 18086213 = 651103668 / (6 + 5 + 1 + 1 + 0 + 3 + 6 + 6 + 8).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651103669) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 9043071 + ... + 9043142.

Almost surely, 2^651103668 is an apocalyptic number.

It is an amenable number.

651103668 is an abundant number, since it is smaller than the sum of its proper divisors (994741806).

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

651103668 is a wasteful number, since it uses less digits than its factorization.

651103668 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18086223 (or 18086218 counting only the distinct ones).

The product of its (nonzero) digits is 25920, while the sum is 36.

The square root of 651103668 is about 25516.7330981064. The cubic root of 651103668 is about 866.7291052320.

The spelling of 651103668 in words is "six hundred fifty-one million, one hundred three thousand, six hundred sixty-eight".