6729969821 has 4 divisors (see below), whose sum is σ = 6756156732. Its totient is φ = 6703782912.

The previous prime is 6729969781. The next prime is 6729969823. The reversal of 6729969821 is 1289699276.

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 6559380100 + 170589721 = 80990^2 + 13061^2 .

It is a cyclic number.

It is not a de Polignac number, because 6729969821 - 2¹⁴ = 6729953437 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 (6729969823) 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, 13093070 + ... + 13093583.

It is an arithmetic number, because the mean of its divisors is an integer number (1689039183).

Almost surely, 2^6729969821 is an apocalyptic number.

It is an amenable number.

6729969821 is a deficient number, since it is larger than the sum of its proper divisors (26186911).

6729969821 is a wasteful number, since it uses less digits than its factorization.

6729969821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26186910.

The product of its digits is 5878656, while the sum is 59.

The square root of 6729969821 is about 82036.3932715231. The cubic root of 6729969821 is about 1888.0103564806.

The spelling of 6729969821 in words is "six billion, seven hundred twenty-nine million, nine hundred sixty-nine thousand, eight hundred twenty-one".