651873865 has 4 divisors (see below), whose sum is σ = 782248644. Its totient is φ = 521499088.

The previous prime is 651873863. The next prime is 651873899. The reversal of 651873865 is 568378156.

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

It can be written as a sum of positive squares in 2 ways, for example, as 351787536 + 300086329 = 18756^2 + 17323^2 .

It is a cyclic number.

It is not a de Polignac number, because 651873865 - 2¹ = 651873863 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (651873863) 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, 65187382 + ... + 65187391.

It is an arithmetic number, because the mean of its divisors is an integer number (195562161).

Almost surely, 2^651873865 is an apocalyptic number.

It is an amenable number.

651873865 is a deficient number, since it is larger than the sum of its proper divisors (130374779).

651873865 is a wasteful number, since it uses less digits than its factorization.

651873865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130374778.

The product of its digits is 1209600, while the sum is 49.

The square root of 651873865 is about 25531.8206362179. The cubic root of 651873865 is about 867.0707247232.

The spelling of 651873865 in words is "six hundred fifty-one million, eight hundred seventy-three thousand, eight hundred sixty-five".