2102820921 has 12 divisors (see below), whose sum is σ = 3043600560. Its totient is φ = 1399022520.

The previous prime is 2102820919. The next prime is 2102820983. The reversal of 2102820921 is 1290282012.

It is not a de Polignac number, because 2102820921 - 2¹ = 2102820919 is a prime.

It is not an unprimeable number, because it can be changed into a prime (2102820721) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 233511 + ... + 242348.

It is an arithmetic number, because the mean of its divisors is an integer number (253633380).

Almost surely, 2^2102820921 is an apocalyptic number.

It is an amenable number.

2102820921 is a deficient number, since it is larger than the sum of its proper divisors (940779639).

2102820921 is a wasteful number, since it uses less digits than its factorization.

2102820921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 476356 (or 476353 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 27.

The square root of 2102820921 is about 45856.5253917041. The cubic root of 2102820921 is about 1281.1523072656.

The spelling of 2102820921 in words is "two billion, one hundred two million, eight hundred twenty thousand, nine hundred twenty-one".