2021131939 has 2 divisors, whose sum is σ = 2021131940. Its totient is φ = 2021131938.

The previous prime is 2021131933. The next prime is 2021131943. The reversal of 2021131939 is 9391311202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2021131939 - 2²³ = 2012743331 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 2021131939.

It is not a weakly prime, because it can be changed into another prime (2021131933) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010565969 + 1010565970.

It is an arithmetic number, because the mean of its divisors is an integer number (1010565970).

Almost surely, 2^2021131939 is an apocalyptic number.

2021131939 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021131939 is an equidigital number, since it uses as much as digits as its factorization.

2021131939 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2916, while the sum is 31.

The square root of 2021131939 is about 44957.0010009565. The cubic root of 2021131939 is about 1264.3429415414.

The spelling of 2021131939 in words is "two billion, twenty-one million, one hundred thirty-one thousand, nine hundred thirty-nine".