651655623 has 4 divisors (see below), whose sum is σ = 868874168. Its totient is φ = 434437080.

The previous prime is 651655591. The next prime is 651655633. The reversal of 651655623 is 326556156.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 651655623 - 2⁵ = 651655591 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (651655633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 108609268 + ... + 108609273.

It is an arithmetic number, because the mean of its divisors is an integer number (217218542).

Almost surely, 2^651655623 is an apocalyptic number.

651655623 is a deficient number, since it is larger than the sum of its proper divisors (217218545).

651655623 is a wasteful number, since it uses less digits than its factorization.

651655623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 217218544.

The product of its digits is 162000, while the sum is 39.

The square root of 651655623 is about 25527.5463568280. The cubic root of 651655623 is about 866.9739512108.

The spelling of 651655623 in words is "six hundred fifty-one million, six hundred fifty-five thousand, six hundred twenty-three".