651680 has 24 divisors (see below), whose sum is σ = 1539972. Its totient is φ = 260608.

The previous prime is 651667. The next prime is 651683. The reversal of 651680 is 86156.

It can be written as a sum of positive squares in 2 ways, for example, as 595984 + 55696 = 772^2 + 236^2 .

It is not an unprimeable number, because it can be changed into a prime (651683) 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, 1877 + ... + 2196.

2⁶⁵¹⁶⁸⁰ is an apocalyptic number.

It is an amenable number.

651680 is an abundant number, since it is smaller than the sum of its proper divisors (888292).

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

651680 is a wasteful number, since it uses less digits than its factorization.

651680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4088 (or 4080 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 651680 is about 807.2669942466. The cubic root of 651680 is about 86.6984761604.

It can be divided in two parts, 651 and 680, that added together give a palindrome (1331).

The spelling of 651680 in words is "six hundred fifty-one thousand, six hundred eighty".