29821828921 has 8 divisors (see below), whose sum is σ = 30596000904. Its totient is φ = 29049886080.

The previous prime is 29821828909. The next prime is 29821828969. The reversal of 29821828921 is 12982812892.

It can be written as a sum of positive squares in 4 ways, for example, as 2253875625 + 27567953296 = 47475^2 + 166036^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 29821828921 - 2⁹ = 29821828409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (29821828991) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 530166 + ... + 583711.

It is an arithmetic number, because the mean of its divisors is an integer number (3824500113).

Almost surely, 2^29821828921 is an apocalyptic number.

It is an amenable number.

29821828921 is a deficient number, since it is larger than the sum of its proper divisors (774171983).

29821828921 is a wasteful number, since it uses less digits than its factorization.

29821828921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1114571.

The product of its digits is 663552, while the sum is 52.

The spelling of 29821828921 in words is "twenty-nine billion, eight hundred twenty-one million, eight hundred twenty-eight thousand, nine hundred twenty-one".