6801780721 has 16 divisors (see below), whose sum is σ = 7450502400. Its totient is φ = 6187215888.

The previous prime is 6801780709. The next prime is 6801780737. The reversal of 6801780721 is 1270871086.

It is a cyclic number.

It is not a de Polignac number, because 6801780721 - 2¹³ = 6801772529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6801780751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22351 + ... + 118756.

It is an arithmetic number, because the mean of its divisors is an integer number (465656400).

Almost surely, 2^6801780721 is an apocalyptic number.

It is an amenable number.

6801780721 is a deficient number, since it is larger than the sum of its proper divisors (648721679).

6801780721 is a wasteful number, since it uses less digits than its factorization.

6801780721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 141228.

The product of its (nonzero) digits is 37632, while the sum is 40.

The square root of 6801780721 is about 82472.9090125964. The cubic root of 6801780721 is about 1894.7018344915.

The spelling of 6801780721 in words is "six billion, eight hundred one million, seven hundred eighty thousand, seven hundred twenty-one".