680961021 has 16 divisors (see below), whose sum is σ = 978949440. Its totient is φ = 418556160.

The previous prime is 680960981. The next prime is 680961053. The reversal of 680961021 is 120169086.

It is not a de Polignac number, because 680961021 - 2¹⁴ = 680944637 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (680961821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 24450 + ... + 44268.

It is an arithmetic number, because the mean of its divisors is an integer number (61184340).

Almost surely, 2^680961021 is an apocalyptic number.

It is an amenable number.

680961021 is a deficient number, since it is larger than the sum of its proper divisors (297988419).

680961021 is a wasteful number, since it uses less digits than its factorization.

680961021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20716.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 680961021 is about 26095.2298514499. The cubic root of 680961021 is about 879.7799988091.

The spelling of 680961021 in words is "six hundred eighty million, nine hundred sixty-one thousand, twenty-one".