2021131849 has 27 divisors (see below), whose sum is σ = 2292804423. Its totient is φ = 1780297200.

The previous prime is 2021131837. The next prime is 2021131891. The reversal of 2021131849 is 9481311202.

The square root of 2021131849 is 44957.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 65723449 + 1955408400 = 8107^2 + 44220^2 .

It is not a de Polignac number, because 2021131849 - 2⁹ = 2021131337 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2021131849.

It is not an unprimeable number, because it can be changed into a prime (2021131949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 30166114 + ... + 30166180.

Almost surely, 2^2021131849 is an apocalyptic number.

2021131849 is the 44957-th square number.

2021131849 is the 22479-th centered octagonal number.

It is an amenable number.

2021131849 is a deficient number, since it is larger than the sum of its proper divisors (271672574).

2021131849 is an frugal number, since it uses more digits than its factorization.

2021131849 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 278 (or 139 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 31.

The cubic root of 2021131849 is about 1264.3429227745.

The spelling of 2021131849 in words is "two billion, twenty-one million, one hundred thirty-one thousand, eight hundred forty-nine".